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Chapter 15
Program
Development and
Programming
Languages
Chapter 15 Objectives
Describe the object-oriented
Explain the six steps in the approach to program
program development life cycle development
Describe top-down program Identify programming
design languages commonly used
today
Explain structured program Identify the uses of application
design and the three basic generators, macros, and RAD
control structures tools
Explain the differences among Describe various Web page
the categories of programming development tools, including
languages HTML, DHTML, XML, and WML
Identify uses of multimedia
authoring packages
Next
p.15.2
What is a Computer
Program?
What is a computer program?
A set of instructions that
directs a computer to
perform tasks
Computer programmers
programming language
• use program
development tools that A set of words, symbols,
and codes that enables a
generate these programmer to
instructions communicate instructions
automatically to a computer
• use a programming
language to write these
Next
p.15.2
instructions themselves
The Program
Development Life Cycle
What is the
program
development
life cycle
(PDLC)?
A set of steps
programmers
use to build
computer
programs
Next
p.15.22 Fig. 15-1
The Program
Development Life Cycle
How is program development related to system
development?
Program development is an ongoing process within
system development
Next
p.15.3 Fig. 15-2
The Program
Development Life Cycle
What initiates the PDLC?
During the analysis
phase of the system
development life cycle
(SDLC), the
development team
recommends how to
handle software needs
If the company
recommends in-house
development,
programmers begin the
PDLC as part of the
implementation phase
Next
p.15.3 Fig. 15-2
The Program
Development Life Cycle
What is the program specification package?
A detailed set of requirements
for a system created by the
systems analyst during the
design phase of the SDLC programming team
Identifies the input, output, A group of
processing, and data programmers who
requirements of each program develop the
and the relationships among programs
programs
The scope of the program
Click to
specification package largely
view video determines how many
Next
programmers work on the
p.15.3
program development
Step 1 – Analyze Problem
What is involved in analyzing the problem?
Analyze the problem
the program(s) Review the program
should solve so you specifications
can begin to develop package
an appropriate
solution
In most cases, the Meet with the
solution requires systems analyst and
users
more than one
program
Three major tasks
Identify each program’s
input, output, and
Next
processing components
p.15.4
Step 1 – Analyze Problem
Why does the programmer review the program
specification package?
Package systems
contains a flowcharts
charts
variety of
deliverables that
identify input, structured
output, design and diagrams English
data requirements
By thoroughly
reviewing the
decision tables and
package, the reports
programmer decision trees
understands the
nature and
Next requirements of screen and report data
p.15. 4
each program layout charts dictionary
Step 1 – Analyze Problem
What is an IPO chart?
Also called a defining diagram
Identifies a program’s inputs, its outputs, and the
processing steps required to transform the inputs into
the outputs
Next
p.15.4 Fig. 15-3
Step 2 – Design Programs
What is involved in designing programs?
Three tasks
• grouping each top-down design
program’s
Task 1
activities into
modules Focuses on what the program
should do
• devising a
solution
algorithm for
each module structured design
• testing the Tasks 2 and 3
solution Determines how to build the
Next algorithms programs based on the
p.15.5 requirements
Step 2 – Design Programs
What is top-down design?
Breaks down the
Identify the the major functions of a
original set of program, called the main routine or
program the main module
specifications
Decompose (break down) the main routine
into smaller,
into smaller sections called subroutines
more
manageable Analyze each subroutine to determine if
sections it can be decomposed further
Continue decomposing subroutines until
each one performs a single function
Click to view Web Link
then click Top-Down Design
Next
A section of a program that performs a
p.15.5
single function is a module
Step 2 – Design Programs
What is a hierarchy chart?
Also called a structure chart or top-down chart
Used to show program modules graphically
Next
p.15. 6Fig. 15-4
Step 2 – Design Programs
What is structured design?
A technique that builds all
program logic from a sequence
combination of three control
basic control structures structure
A control structure is a
design that determines selection
the logical order of control
program instructions structure
Click to view
Web Link
• also called a construct repetition
then click Each module typically control
Structured
Design contains more than one structure
Next
control structure
p.15.6
Step 2 – Design Programs
What is a sequence control structure?
Shows one or
more actions
following each
other in order
Actions
• inputs
• processes
• outputs
Next
p.15.7 Fig. 15-5
Step 2 – Design Programs
What is a selection control structure?
Tells the
program which
action to take, if-then-else
based on a control structure
certain condition
Two common
types of
selection control case control
structures structure
Next
p.15.7
Step 2 – Design Programs
What is an if-then-else control structure?
Allows a program to evaluate the condition and yields
one of two possibilities: true or false
If the result of the condition is true, the program
performs one
action
If the result is
false, the
program
performs a
different (or
possibly no)
Next
action
p.15.7 Fig. 15-6
Step 2 – Design Programs
What is a case control structure?
A condition can yield one of three or more
possibilities
Next
p.15.7 Fig. 15-7
Step 2 – Design Programs
What is a repetition control structure?
Also called the
iteration control
structure or a loop do-while
control
Used when a
structure
program performs
one or more
actions repeatedly
as long as a
certain condition is do-until
control
met
structure
Two forms
Next
p.15.8
Step 2 – Design Programs
What is a do-while control structure?
Repeats one or more
times as long as a
condition is true
• Tests a condition at the
beginning of the loop
• If the result is true, the
program executes the
action(s) inside the
loop
• Program loops back
and tests the condition
again
Next • Looping continues until
p.15.8 Fig. 15-8 the condition becomes
false
Step 2 – Design Programs
What is a do-until control structure?
Tests the condition
at the the end of the
loop
The action(s) will
always execute at
least once
Continues looping
until the condition is
true, and then stops
Next
p.15.8 Fig. 15-9
Step 2 – Design Programs
What are the guidelines of a proper program?
dead code
The program,
each of its Any code, or program instruction,
modules, and that a program never executes
each of its
control infinite loop
structures must A set of instructions that repeats
have continuously
• No dead code
entry point
• No infinite
loops The location where a program, a
module, or a control structure begins
• One entry
point
exit point
Next
p.15.8
• One exit point
The location where it ends
Step 2 – Design Programs
How are entry and
exit points shown?
Program
modules often
have control
structures
nested inside
one another
Each control
structure should
have one entry
point and one
exit point
Next
p.15.9 Fig. 15-10
Step 2 – Design Programs
What is a solution algorithm?
Also called program
logic
A graphical or written program flowchart
description of the
step-by-step
procedures in a Nassi-
Schneiderman
module charts
To help develop a
solution algorithm,
programmers use pseudocode
design tools
Next
p.15.9
Step 2 – Design Programs
What is a program
flowchart?
Graphically shows
the logic in a solution
algorithm
Follows a set of
standards published
by the American
National Standards
Institute (ANSI) in the
early 1960s
Next
p.15.9 Fig. 15-11
Step 2 – Design Programs
How is a program flowchart drawn?
Most
symbols
connect
with solid
lines
showing the
direction of
the program
Dotted lines
connect
comment
symbols
comment symbol or
Next annotation symbol
p.15.10 Fig. 15-12
Explains or clarifies logic
Step 2 – Design Programs
What is flowcharting software?
Used to
develop
flowcharts
Makes it
easy to
modify and
update
flowcharts
Click to view Web Link
then click Flowcharting Software
Next
p.15.10 Fig. 15-13
Step 2 – Design Programs
What is a Nassi-Schneiderman (N-S) chart?
Graphically shows the logic in a solution algorithm
Sometimes called structured flowcharts
Next
p.15.11 Fig. 15-14
Step 2 – Design Programs
What is
pseudocode?
Uses a condensed
form of English to
convey program
logic
Also uses
indentation to
identify the three
basic control
structures
Next
p.15.12 Fig. 15-15
Step 2 – Design Programs
What is a quality review?
The programmer
checks the logic
for correctness
and attempts to
uncover logic
errors
logic error
Two techniques
for reviewing a A flaw in the design
solution that causes
inaccurate results
algorithm
• desk check
• structured
Next walkthrough
p.1512
Step 2 – Design Programs
What is a desk check?
The use of test 1. Developing sets of test data (inputs)
data to step
though a 2. Determining the expected result
program’s logic (output) for each set of data, without
using the solution algorithm
Test data is
sample data that 3. Stepping through the solution
mimics data the algorithm using one set of test data
program might and writing down the actual result
obtained (output) using the solution
process once it is
algorithm
in production
Involves five steps 4. Comparing the expected result from
Step 2 to the actual result from Step 3
Next
p.15.12 5. Repeating Steps 3 and 4 for each set
of test data
Step 2 – Design Programs
What is a structured walkthrough?
A more formal technique
for checking the solution
algorithm
The programmer explains
the logic of the algorithm Detecting errors
while members of the and making
programming team step improvements early
in the PDLC
through the program logic reduces the overall
Purpose is to identify time and cost of
errors in the program logic program
and check for possible development
Next
improvements in program
p.15.12
design
Step 3 – Code Programs
What is involved in coding programs?
Two steps
• translating the solution
algorithm into a
programming language
• entering the
programming syntax
language code into The set of grammar
the computer and rules that
specifies how to write
Each of the many instructions for a
programming languages solution algorithm
has a particular syntax
Next
p.15.13
Step 3 – Code Programs
How are programs documented?
A programmer should take time to document the program code
thoroughly
Comments or remarks are included in a program as documentation
Global comments explain the program’s purpose and identify the
program name, its author, and the date written
Internal comments explain the purpose of the code statements
within the program
global
comments
Next internal
p.15.13 Fig. 15-16 comments
Step 4 – Test Programs
What is involved in testing programs?
Goal is to ensure syntax errors
the program runs Occur when the code violates the syntax,
correctly and is or grammar, of the programming
error free language
Two typical types Usually discovered the first time a
of errors program code is executed on the
computer
• syntax errors
• logic errors logic errors
Flaw in the design that generates
inaccurate results
Next Systems analyst develops test data
p.15.13 including both valid and invalid input
data
Step 4 – Test Programs
What is a run time error?
A program failure
occurring while a
program is being
executed
Programmers use test
data to deliberately
cause a run time error
in order to test the
program
Next
p.15.13
Step 4 – Test Programs
What is debugging?
The process of
locating and
correcting the
syntax and logic
errors in a
program
Errors themselves
are the bugs
The first bug was
said to be a moth
lodged in a
computer's
electronic
components
Next
p.15.14 Fig. 15-17
Step 4 – Test Programs
What is a debug utility?
Also called a
debugger
millennium bug
Allows you to
identify syntax Also called the Y2K
errors and to find bug
logic errors Took effect when the
You can examine computer date rolled
program values over to January 1,
while the 2000
program runs in Non Y2K compliant
slow motion computers read the
date as 01/01/00
Next
p.15.14
Step 5 – Formalize
Solution
What is involved in formalizing a solution?
The programmer performs two
activities hierarchy chart
• review the program code
– look for any dead code solution algorithm in the
and remove it form of a program
– run the program one flowchart, and N-S chart,
final time to verify it still or pseudocode
works
• review all the test data
documentation
– ensures all
documentation is program code listings
complete and accurate that contain global and
Next
p.15.15
– includes a number of internal comments
types of documentation
Step 6 – Maintain
Programs
What is involved in maintaining programs?
Two activities
• correcting errors
• adding enhancements When users identify errors or
enhancements, they typically
– involves modifying notify the systems analyst
existing programs to
improve their
functionality
When a program is The systems analyst
implemented, or placed contacts and meets with a
into production, users programmer
interact with the programs
• programs process They begin to analyze the
actual, or live, problem or enhancement,
Next transactions which is Step 1 of the
p.15.15 • users identify errors PDLC
and enhancements
Programming Languages
and Program Development
Tools
What are programming languages and program
development tools?
programming language
program development tool
A set of words, symbols,
Consists of user-friendly
and codes that enables a
software products
programmer to
designed to assist both
communicate a solution
programmers and
algorithm to the computer
nontechnical users with
the creation of information
system solutions
Next
p.15.16
Categories of
Programming Languages
What are the categories of programming
languages?
Five major categories of programming languages
assembly languages
machine languages
Click to third-generation
view
animation languages
fifth-generation
Click to fourth-generation languages
view video languages
Next
p.15.16
Categories of
Programming Languages
What are low- and high-level programming
languages?
Languages are classified as either low level or high level
low-level language high-level language
A programming language A language that is machine
that is machine dependent independent
machine-dependent language machine-independent language
Only runs on one particular Can run on many different
computer types of computers and
operating systems
Next
machine and assembly third-generation, fourth-
p.15.16
languages are low-level generation, and fifth-generation
languages are high-level
Categories of
Programming Languages
What is machine
language?
The first generation of
programming languages
The only language the
computer directly
understands
Uses a series of binary
digits (1s and 0s) or a
combination of numbers
and letters that represent
Click to binary digits
view
animation Binary digits correspond
Next
to the on and off electrical
p.15.16 Fig. 15-18
states of a computer
Categories of
Programming Languages
What is assembly
language?
The second generation of
programming languages
A programmer writes
instructions using symbolic
instruction codes
symbolic instruction
codes
Also called mnemonics
Next Meaningful abbreviations
p.15.16 Fig. 15-19 and codes
Categories of
Programming Languages
What are features of assembly languages?
symbolic address Source program
A meaningful name that The program that contains
identifies a storage location the assembly language code
macro
Assembler
Generates multiple machine
Converts the assembly
language instructions for a
language source program
single assembly language
into machine language so
instruction
that the computer can
Saves the programmer time understand it
Next
during program development
p.15.17
Categories of
Programming Languages
What is a third generation language (3GL)?
Uses a series of English-like words to write instructions
A procedural language
• requires the program instructions tell the computer
what to accomplish and how to do it
Click to
view
animation
Next
p.15.18 Fig. 15-20
Categories of
Programming Languages
What is a compiler?
Converts the entire source source program
program into machine The 3GL code
language before executing it
The compiler checks the
source program’s syntax object code
Makes sure the program Also called an object program
properly defines the data it
will use in calculations or The machine language version that
comparisons results from compiling the 3GL
Produces a program
listing which contains
the source code and a
list of any syntax errors
Translates an entire
program before
Next
executing it
p.15.18 Fig. 15-20
Categories of
Programming Languages
What is an interpreter?
Reads a code statement
Converts it to one or more machine language
instructions
Executes those machine language instructions
Translates and executes one program code statement at
a time
Does not
produce an
object program
Next
p.15.18 Fig. 15-21
Categories of
Programming Languages
What is a fourth-generation language (4GL)?
Uses English-like
statements
The syntax is closer to
human language than
that of a 3GL
A nonprocedural
language
• programmer only
specifies what the
program should
accomplish
without explaining
how
• many 4GLs work
with a database
Next
and its project
p.15.19 Fig. 15-22 dictionary
Categories of
Programming Languages
What are some examples of 4GLs?
report writer
SQL
Also called a report
A query language generator
enabling users and
Software that allows you
programmers to
to design a report on the
retrieve data from
screen, retrieve data into
database tables
the report design, and
then display or print the
report
Builds a 4GL query that
Next enables you to access
p.15.19 the data
Categories of
Programming Languages
What is a fifth-generation language (5GL)?
One that provides a visual or
graphical interface for creating
the source code
Often converts the source
code to machine language
using a 3GL or 4GL
compiler
Object-oriented and
Web development
tools sometimes use
a 5GL such as Visual
Next Basic
p.15.20 Fig. 15-25
Object-Oriented Program
Development
What is the object-oriented (OO) approach?
The programmer object
can package the
An item that can contain both data and the
data and the
procedures that read or manipulate that data
program (or
procedure) into a
single unit, method or operation
called an object The procedure in the object that contains
When the activities that read or manipulate the data
structure of an
object changes, attributes or variables
any program that
accesses the The data elements
object
automatically encapsulation or information hiding
Next
p.15.20
accesses the The concept of packaging methods and
change attributes into a single object
Object-Oriented Program
Development
What is a class?
A larger category of objects
Each object in a class shares methods and attributes
that are part of the original object
A generalization
hierarchy shows
relationships
between classes
of an object
Next
p.15.20 Fig. 15-23
Object-Oriented Program
Development
What are some terms related to classes?
Each class can have one or more subclasses
The higher-level class is called a superclass
Inheritance is the concept of lower levels inheriting
methods and
attributes of
higher levels
An object
instance is a
specific
occurrence of
an object or
object class
A message tells
Next an object what
p.15.20 Fig. 15-23 to do
Object-Oriented Program
Development
What is the Object Management Group (OMG)?
An international
UML (Unified Modeling
organization that Language)
establishes
Contains the standard
guidelines and
notation for analysis,
specifications for design, and documentation
OO application for the OO approach
development
Has adopted UML CORBA (Common Object
and CORBA as Request Broker Architecture)
standards Defines how objects in
separate programs on a
Next
network can communicate
p.15.21
with each other
Object-Oriented Program
Development
What is object-oriented programming (OOP)
language?
A language that uses the
OO approach
An OOP is event driven
• checks for and
event
responds to a set of
events The OOP term for
message
C++ is a complete object-
oriented language
Click to view Web Link
then click Object-Oriented
Programming Languages
Next
p.15.21
Programming Languages
What are the most widely used programming
languages?
BASIC
Hundreds of
programming
languages exist Visual Basic
A few are used
widely enough to COBOL
be recognized as
standards C
Most are high-
level languages C++
Next
RPG
p.15.22
Programming Languages
How can you compute gross pay?
Figures on the
1. Multiply the regular time hours worked
following slides
by the hourly rate of pay to obtain the
show program regular time pay
code in several
Regular pay = regular hours x hourly rate of pay
programming
languages 2. Multiply the overtime hours by 1.5
times the hourly rate of pay to obtain
The code solves the overtime pay
a simple payroll
Overtime pay = overtime hours x 1.5 x hourly rate of
problem – pay
computing the
3. Add the regular time pay and the
gross pay for an
overtime pay together
Next employee
p.15.22 Gross pay = regular time pay + overtime pay
Programming Languages
What is BASIC?
Beginner's All-purpose Symbolic Instruction Code
Developed by John Kemeny and Thomas Kurtz in the mid-
1960s at Dartmouth College
Designed for use as a simple, interactive problem-solving
language
Next
p.15.22 Fig. 15-24
Programming Languages
What is Visual Basic?
A Windows-based application that assists programmers
in developing other event-driven Windows-based
applications
Developed by Microsoft Corporation in the early 1990s
Click to
view Web
Link
then click
Visual
Basic
Next
p.15.22 Fig. 15-25
Programming Languages
How is a Visual Basic application created?
4:
3:
2: tests
Step 1: Programmer writes
assigns user interface.pay
designs properties to each
the application. Gross
code and assigns it to the
COMPUTE button.
object onafter Hours
Regular Time form. Objects
displays the COMPUTE
Worked,text boxes,Hours
button is clicked.
include Overtime
command buttons, labels,
Worked, and Hourly Pay
Ratethe form boxes, in
and are text itself.
which the user enters data.
COMPUTE and CLEAR are
command buttons. All
other objects are labels.
Next
p.15.23 Fig. 15-25
Programming Languages
What is COBOL?
COmmon Business-Oriented Language
Developed out of a joint effort between the United States
government, businesses, and major universities in the early 1960s
Naval officer Grace Hopper was a prime developer of the COBOL
language
One of the
more widely
used
procedural
programming
languages for
business
applications
Next
p.15.24 Fig. 15-26
Technology Trailblazer
Grace Hopper
Programmed the Mark I
‘computer engine’ to find the
angles to aim naval guns in
varying weather conditions
Helped build and program
several other early
computers
Credited with finding the
first computer ‘bug’
Click to
view Web Developed the first compiler
Link
then click Created the FLOW-MATIC
Grace
Hopper programming language that
Next laid the foundation for
p.15.24 COBOL
Programming Languages
What is C?
Developed in the early 1970s by Dennis Ritchie at Bell
Laboratories
Originally designed for writing system software
A powerful language that requires professional programming
skills
Next
p.15.25 Fig. 15-27
Technology Trailblazer
Dennis Ritchie
Developed C at Bell
Labs in the early
1970s
Tweaked an earlier
programming
language, B, to
make it portable
C became extremely
popular outside of
Bell Labs after 1980
Awarded the
National Medal of
Technology in 1999
Click to view Web Link
then click Dennis Ritchie
Next
p.15.25
Programming Languages
What is C++?
Developed in the 1980s by Bjarne
Sroustrup at Bell Laboratories
An object-oriented programming
C#
language
An extension of the C programming A newer
language programming
language that
Includes all the elements of the C combines features
language plus has additional of C and C++
features for working with objects,
Best suited for
classes, events, and other object-
development of
oriented concepts Web applications
Click to view Web Link
then click C++
Next
p.15.25
Programming Languages
What is RPG?
Report Program Generator
Introduced by IBM in the early 1960s to assist
businesses in
generating reports
Businesses also
use RPG for
complex
computations and
file updating
A nonprocedural
language
Next
p.15.26 Fig. 15-28
Programming Languages
What are some other programming languages?
Next
p.15.26 Fig. 15-29
Program Development
Tools
What are program development tools?
User-friendly software
products designed to help both
program developers and
nontechnical users create application generators
solutions to information
requirements
Empower nontechnical users
by giving them the ability to
write simple programs on their
macros
own
Allows programmers and IT
professionals to focus
development efforts on larger
projects RAD tools: Visual Basic,
Next Delphi, and PowerBuilder
p.15.27
Program Development
Tools
What is an application
generator?
Sometimes called a program generator
A program that allows you to build an
application without writing the extensive
code required by a 3GL
Developer works with menu generator
menu-driven tools that Allows the developer
have graphical user to create a menu, or
interfaces list of choices, for the
application options
Typically includes a
report writer,
Next
form, and menu
p.15.27 generator
Program Development
Tools
What are report writers and
forms?
A report writer allows
you to design a report
on the screen,
retrieve data into the
report design, and
then display or print
the report
A form is a window
on the screen that
provides areas for
entering or changing
Next
data in a database
p.15.27 Fig. 15-30
Program Development
Tools
What is a macro?
A series of statements that
instructs an application
how to complete a task macro recorder
Can automate routine, Used to automate
repetitive, or difficult tasks a routine or
in an application such as repetitive task
word processing,
Records all
spreadsheet, or database
actions until
programs turned off
You usually create a macro
in one of two ways
• record the macro
Next
p.15.28
• write the macro
Program Development
Tools
What is Visual Basic for Applications (VBA)?
Used to write your
own macros
Macros use the
Loan Data
three basic
structured button
programming
constructs
(sequence, Macro
selection, and dialog
iteration) within box
modules
Also use objects,
classes, and other VBA macro used
object-oriented to automate an
concepts auto loan
Next Macro dialog box in Excel window
computation
p.15.28 Fig. 15-31 guiding the user through the data
entry process
Program Development
Tools
What is rapid application development (RAD)?
The concept of developing
software throughout the system
development process Visual Basic
A common technique is
prototyping
• a prototype is a working
model of the proposed
Delphi
system
RAD tools are used to develop
Click to view
Web Link easy-to-maintain, component-
then click
Rapid
based applications
Development • component is another term
Application
PowerBuilder
Next for object
p.15.29
• three popular RAD tools
Program Development
Tools
What are Visual Basic and Delphi?
Visual basic
• A Windows-based
application that assists
programmers in developing
other event-driven Windows-
based applications
• One of the first programming visual programming
environments to provide a environment (VPE)
visual programming Allows developers to
environment (VPE) drag-and-drop objects
Delphi to build programs
• Offers a drag-and-drop VPE
• Provides full object-oriented
Next capabilities
p.15.29
Program Development
Tools
What is PowerBuilder?
Uses a
proprietary
object-oriented
language for its
application
development
Language is
called
PowerScript
Can create
powerful
applications
Next
p.15.30 Fig. 15-32
Company on the Cutting
Edge
Developer of PowerBuilder
Enterprise, Powersoft,
PowerStudio, and Adaptive
Component Architecture
Selected as the company
with Best Customer
Support in the computer
industry by InfoWorld
readers
Click to
view Web Products help developers
Link
then click efficiently create Internet
Sybase
applications and
Next
client/server programs
p.15.30
Web Page Program
Development
What is involved in developing Web pages?
A Web page is a
linked document HTML
that can contain Scripts, Applets,
text, graphics, Servlets, and
video, and audio ActiveX Controls
posted on the World Java, JavaScript,
Wide Web VBScript, and Perl
Web page authors, Dynamic
HTML
the designers of
XHTML, XML,
Web pages, use a
and WML
variety of
Next techniques to Web page authoring
p.15.31 software
develop Web pages
Web Page Program
Development
What is hypertext markup language (HTML)?
A special formatting
language that tags or markups
programmers use to
Codes that specify links
create Web pages
to other documents and
View Web pages written indicate how the Web
with HTML in a Web page displays when
browser viewed on the Web
Not actually a
programming language
• a language with
<HR>
specific syntax rules Web page
for defining the
placement and format
of text, graphics, <B> A file that contains
both text and HTML
<P>
Next
video, and audio on a tags
p.15.31
Web page
Web Page Program
Development
How does
HTML code
look?
HTML code can be
written using any
text editor or
entered into any
standard word
processing
software package
Save the code as
an ASCII file with
an .htm or .html
Next extension
p.15.31 Fig. 15-33
Web Page Program
Development
How does HTML relate to a Web page?
Web page
created
from part
of the
Web code
shown in
Figure
15-33
Next
p.15.31 Fig. 15-34
Web Page Program
Development
How are dynamic elements added to a Web page?
Small programs script
called scripts, An interpreted program that runs on
applets, servlets, the client
and ActiveX
controls are used applet
Also usually runs on the client,
to add dynamic
but it is compiled
content and
interactive servlet
elements An applet that runs on the server
• short
programs that ActiveX control
run inside of A small program that runs on your
another computer, instead of the server
Next
program Uses ActiveX technology, a set of object-
p.15.32
oriented technologies by Microsoft
Web Page Program
Development
What are some special effects that can be added
with scripts, applets, servlets, and ActiveX
controls?
counter
Add multimedia effects
Tracks the number of
• animated graphics
visitors to a Web site
• scrolling messages
• calendars
• advertisements image map
Include interactive A graphical image that points to a
capabilities URL
• cookies
• shopping carts When you click a certain part of the
• games graphical image, your Web browser
sends the coordinates of the clicked
Next • counters
location to the Web server, which in
p.15.32 • image maps turn locates the corresponding URL
• processing forms
Web Page Program
Development
What is a processing
form?
Collects data
from visitors
to a Web site,
who fill in
blank fields
and then click
a button that
sends the
information
Activates with
a script or
applet
Next
p.15.32 Fig. 15-35
Web Page Program
Development
What is the common gateway interface (CGI)?
The communications
standard that defines how
a Web server
communicates with You can download
outside sources CGI programs from
The program that the Web, purchase
them, or write your
manages the sending and own
Click to
view Web receiving across the CGI
Link
then click
is a CGI script, or CGI
CGI
Programs
program
Next
p.15.33
Web Page Program
Development
How does a CGI program work?
Step 1: Programmer
Step 3: When a user
4: The CGI
Step 2: Webmaster Web server
stores a request, it in a
submitsCGI programis sent
creates a receives
program link
special folder on the
to the CGI program. The
information from the
between CGI
Web server, such as
CGI program contacts the
database,
program and Web
/cgi-bin.
database and requests
page. When a user
assembles it in an
information for the user. In
HTML format, and
displays the Web
this case, it looks for a
sends it to the
page, the CGI
movie titled Secret Garden.
user’s Web
program browser.
automatically starts.
Next
p.15.33 Fig. 15-36
Web Page Program
Development
What is a scripting language?
An interpreted
language that
typically is Java
easy to learn
and use JavaScript
Often used to
write CGI
scripts
VBScript
Perl
Next
p.15.34
Web Page Program
Development
What is Java?
Developed by Sun
Microsystems JavaBeans or
A compiled object-oriented Beans
programming language used Code segments
to write stand-alone used to create a
applications, as well as Java application
applets and servlets
Platform
Source code is compiled into independent
bytecode, instead of object
code, which is executed by a
Java interpreter
Click to view Web Link
then click Java
Next
p.15.34
Web Page Program
Development
How does
a sample
of Java
code look?
Java applet
code
resulting
screen
Click to
view video
Next
p.15.34 Fig. 15-37
Web Page Program
Development
What is JavaScript?
An interpreted language that The result of a joint
allows the programmer to venture between Sun
add dynamic content and Microsystems and
interactive elements to a Netscape
Web page Communications
JavaScript code is inserted Corporation
directly into an HTML
document
Much simpler than Java open language
To run JavaScript, your Anyone can use it
browser must support it without purchasing
• Netscape supports it a license
Next
• Internet Explorer supports
p.15.35
a subset called JScript
Web Page Program
Development
How does a sample of JavaScript code
look?
JavaScript
code
Pop-up
window
made with
JavaScript
code
Click to view Web Link
then click javaScript
Next
p.15.35 Fig. 15-38
Web Page Program
Development
What are other scripting languages?
VBScript (Visual Basic Scripting Edition)
A subset of the Visual Basic language
Allows you to add intelligence and interactivity to Web pages
You embed VBScript code directly into an HTML document
Perl (Practical Extraction and Report Language)
First developed by Larry Wall at NASA’s Jet Propulsion
Laboratory
Originally a procedural language similar to C, but now is
Next an interpreted scripting language
p.15.36
Web Page Program
Development
What is dynamic HTML (DHTML)?
A newer When you point to the
type of Recreational Vehicles
link, image to the right is
HTML a camper and text
discusses
Allows you communication from
to include your RV
more
graphical
interest and
interactivity
When you point to the
Rural Regions link,
Click to view Web Link
image to the right is a
then click Dynamic HTML
farmer and text
Next
discusses calling from
p.15.36 Fig. 15-39
the farm
Web Page Program
Development
What are features of DHTML?
DHTML works by using the document object model,
style sheets, and scripting languages
document object
model (DOM) cascading style sheets
(CSS)
Defines every item on
a Web page as an Contain the formats for
object how a particular object
should display in a Web
Allows you to change browser
properties, such as
color or size, of any or
Next
all of these objects on
p.15.37
the Web page
Web Page Program
Development
What are XHTML, XML, and WML?
XML (eXtensible WML (wireless
XHTML
Markup Language) markup language)
(eXtensible HTML)
Allows Web page Allows Web page
Includes features of
developers to create developers to
HTML and XML
customized tags, as design pages
well as use specifically for
predefined tags microbrowsers
Uses XSL A subset of XML
(eXtensible
Stylesheet Uses the wireless
Language) as its application
Click to view Web Link
style sheet protocol (WAP)
then click WML
Next specification
p.15.37
Web Page Program
Development
What is Web page authoring software?
Sometimes called an
HTML editor Adobe GoLive
Allows you to create
sophisticated Web
pages that include Lotus FastSite
graphical images,
video, audio,
Macromedia
animation, and other
Dreamweaver
special effects
Generates HTML
tags from your Web Macromedia Flash
page design
Next
p.15.38 Microsoft FrontPage
Multimedia Program
Development
What is multimedia authoring software?
Also called
authorware
Allows you to Toolbook
combine text,
graphics,
animation, audio,
and video into an Authorware
interactive
presentation
Director
Next
p.15.38
Multimedia Program
Development
How is multimedia authoring software used?
Computer-based
training (CBT) or
computer-aided
instruction (CAI)
CBT software is
called
courseware
Web-based
training (WBT)
Distance
learning,
distance
education, or
Next
online learning
p.15.38 Fig. 15-40
Multimedia Program
Development
What is ToolBook?
From click2learn.com, Inc.
Has a graphical user interface
Uses an
object-oriented
approach
Can convent
multimedia
applications
into HTML and
Java
Next
p.15.40 Fig. 15-41
Multimedia Program
Development
What is Authorware?
Software developed by
Macromedia magazines
Multimedia authoring
software package
catalogs
Provides the tools
developers need to build
interactive multimedia
reference titles for CD-
training and educational ROMs and DVD-ROMs
programs
Powerful authoring
environment for applications for
kiosks
Next development of
p.15.40
interactive multimedia
Multimedia Program
Development
What is Director?
Also from An application created using Director
Macromedia
A popular
multimedia
authoring program
with powerful
features
Allows you to
create highly
interactive
multimedia
applications
Includes Lingo, a
built-in object-
oriented scripting
Next language
p.15.40 Fig. 15-40
Selecting a Programming
Language or Program
Development Tool
What factors should be considered in selecting a
programming language?
1. Standards of the organization
Standards Interface
2. Interface with other programs
3. Suitability of the language to
the application Portability
Suitability
Next
p.15.40 4. Portability to other systems
Company on the Cutting
Edge
Macromedia
Software used by more
than 1 million
professional Web
developers to author,
produce, deliver, and
analyze Web content
Dreamweaver is the
leading platform in 70
percent of the market
Flash Player is the most
Click to view
widely Web-distributed
Web Link software in history
then click
Macromedia
Nearly 20 million users
Next have registered their
p.15.41
copies of Shockwave
Summary of Program
Development and
Programming Languages
What is a computer program?
The program development life cycle
Step 1 – Analyze problem
Step 2 – Design programs
Step 3 – Code programs
Step 4 – Test programs
Step 5 – Formalize solution
Step 6 – Maintain programs
Programming languages and program
development tools
Summary of Program
Development and
Programming Languages
(cont.)
Categories of programming languages
Object-oriented program development
Programming languages
Program development tools
Web page program development
Multimedia program development
Selecting a programming language or
program development tool
Chapter 15 Complete
