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BEGINNER'S GUIDE TO PROGRAMMING
Why Should I Do It?
administrator Common Programming Questions
Programming is fun. It is a stimulating creative process by which your mind conceives of a goal
(some result you wish to achieve) and you create it.
What is it you want to achieve? Programming for some is a fun hobby, while others a necessary
evil. If there is a specific program you want to create, and you aren’t really interested in learning
program, you will first want to research and find out if the tool already exists. If something out
there does what you want, don’t push yourself.
If you want to learn how to program just to see how programming works, then you have come
to the right place. This website will guide you as to a correct programming language and
provide a tutorial on that language to demonstrate to you some of the inner workings of that
language.
If you want to create games, be aware it is a long road. It is not impossible of course, and it is a
very satisfying journey if you are truly interested in how games work and creating your own.
This website has a page devoted entirely to game programming.
If you have a need for a certain utility or tool and/or think there might be one in the
marketplace, we can guide you as to the best route for you to follow.
What exactly is programming?
administrator Common Programming Questions
“Programming” is the process of writing instructions that the programming language uses to tell
the computer what to do. Of course the explanation can get much more detailed and complicated
than that, but that is a good basic idea for the beginner. Programming can be done on any
platform (“platform” generally refers to the combination of hardware and software you are
using – for example, AMD processor and Windows XP) you are likely to be using to read this
page. We will assume that most beginners are likely to be using Windows, but you can write
similar programs for other platforms such as those using Unix, Linux, or MAC operating
systems.
Can I figure this programming stuff out?
administrator Common Programming Questions
Although much of the material you might pick up in a bookstore or see on the internet seems
very dense and hard to understand, programming isn’t all that difficult. Anyone who can follow
a set of rules and use logic to solve a problem can program. Anyone functioning in society
today is capable of that! Programming highly complex projects obviously gets more difficult,
but let’s not put the cart before the horse.
To program successfully, you need to be able to write instructions in a programming language
(rules), and order those instructions to achieve the results you desire (logic). You do this every
day: To cook food (even if you microwave), you take ingredients, follow some steps, and get
the result of the fully prepared food. To get ready for bed at night, you do a few tasks a certain
way – brush your teeth, change clothes, get in bed, etc. – and in a certain order to achieve the
result of being ready to properly sleep.
If you can think these things through, you can program. The rest is just semantics.
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One overriding concept to keep in mind – programs cannot read your mind. When
programming, the computer will only do exactly what you tell it, no more, no less. If the
program has a result that is not what you intended, you either forgot to tell it something it
needed to know or do, and told it to do something incorrectly or in an unintended way. This
may seem to be a simple concept, but it is very important to keep in mind when thinking
through your program writing.
How does it work?
administrator Common Programming Questions
You don’t need to know this stuff in order to start writing programs, but if you would like an
idea what is going to go on behind the scenes, read on.
If you are going to write full fledged programs in a language like Visual Basic, C, C++ or Java,
you are writing in what is called a high level language. This is language that is created to read in
easily understandable usage and formatting, although you may not think so at first! When you
compile the program, the compiler first checks to make sure you follow the structure and rules
of the language. After that, the program you wrote is broken down into machine code that can
be read by the computer. Essentially, machine code is what you may have seen referred to in the
past as binary code – numbers like “00101101”. Everything you write is broken down to its base
level - sets of zeros and ones that can be understood by the end machine.
If you are writing in a web formatting language like HTML or web scripting language like PHP,
the process is a little different. Ultimately everything is still broken down into machine code so
the processor can interpret it, but you are using a script rather than a full fledged compiled
programming language. The script is run through the interpreter at the time the script is called,
and translated into results on the browser screen. It is never compiled, rather it is a set of
commands the browser is prepared to deal with when it is called.
Stuff you don’t really need to know at this point, but you might find interesting:
There are two main design processes languages use today : Functional/algorithm based and
Object Oriented.
Functional program design was the standard for many years, and even today most things can be
accomplished using a simple functional approach. The functional approach can be thought of
this way: Ok, I have some data here. Do step one. Ok, do step two. Do I need to go to step three
or four? Ok, go to step four. On and on until the program execution is completed. Sounds
logical, eh? It is still the way I find easiest to understand programming for the beginner.
Objected oriented programming (OOP) is considered the new paradigm in program design. C++
and Java are both objected oriented languages, though you can still use them as functional
languages. We don’t think learning object oriented design should be a priority for the beginner –
this site is designed to get you where you want to go with minimal confusion, and trying to
understand OOP is frankly quite confusing for the beginner. After the beginner understands
functional programming and how it works, then perhaps trying to learn OOP and its benefits are
justified. Frankly, most people never need to get that far to do what they want. If you have the
intellectual curiosity, or the career need, you will continue on a course to OOP, otherwise it will
just stall your progress in writing working programs that are useful to you. That being said,
understand that OOP (when fully understood and used) allows what is considered a more
“elegant” design and increased usefulness of your programs by advanced programmers (not
beginners) and if you move on to writing more advanced programs you may likely work your
way into OOP. Regardless of what some programmers might say, you can have a fully
satisfying programming career without ever using OOP.
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How do I program?
administrator Common Programming Questions
There are basically two steps to any program. Programming enthusiasts may disagree with me
here, and as far as deep programming doctrine they would be correct. As far as the new user is
concerned though, there are two steps you need to know right now. Write and compile.
Writing the program is the process of breaking out your instructions step by step and instructing
the compiler to do those things in the proper programming language. Your first step is to figure
out exactly what you want your program to do, step by step. It is helpful to write this out on
paper (often called “psuedocode”). Once you gain more experience you will start to see the
value in doing this, so don’t worry too much about it right now. Keep in mind though when you
write larger programs that have 10, 20, or even 100 or more steps and/or options available to the
program or user, mapping everything out on paper first will be an invaluable tool. One you have
your steps figured out, you will want to write your program in the language you have chosen.
Whatever programming language you choose, it will have specific word and styles to do
different things. Much like we use words and punctuation every day, so do programs. The good
news is that it really doesn’t take long to get familiar with a language and style. The bad news is
most languages are quite different in the verbiage and punctuation! Don’t worry about that for
now though, your main goal is to become proficient in a language that is useful to you.
Compiling your program takes your written program in text form and translates it into an
executable (usually) that can be run by the machine. For example, if you wrote a simple
program to display a picture in a window, when you compile the program it takes the code you
wrote and creates the executable command you click on in windows to run the program. When
you run the program, the picture displays as you have commanded it to.
After you write and compile, you will want to test your program to see if you are getting the
desired results. If you aren’t getting the results you would like, you will then need to test your
program you errors (commonly called “debugging”).
What do I need to know no matter what programming language I use?
administrator Common Programming Questions
There are some things you will need to use no matter what programming language you use.
Listed below are some concepts that apply to most (if not all) languages. Read through them and
you will start to get an idea what types of things you will need to learn to begin programming. If
it seems like a lot right now, don't worry! The basic concepts you need to know you will learn
one by one as you start programming. The concepts will build on each other until it all comes
together and makes sense!
Variables – variables in programming are similar to variables you might remember from your
algebra classes. Instead of just holding numbers, variables in programming can hold numbers or
text (among other things). Commonly used variable types are: Integer – a whole number (no
decimal), Double or Float – a number with a possible decimal, String – a string of letters, words
or numbers looked at as text, Boolean – a variable that can be set to either TRUE or FALSE,
useful in executing program controls once you get more involved in programming.
Operators – Operators are what you use in a program to work on a variable. Common operators
are + (addition) , -(subtraction), /(division), *(multiplication), =(assignment of value, as in
X=4), ++(increments an integer by 1), --(subtracts 1 from an integer).
Braces – {} - also called curly braces. These are used to control program flow. Everything in
the braces is to be executed as a group.
Functions – Again similar to their usage in algebra, functions are used to do some work (often,
but not necessarily, on a variable) to obtain a result.
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Include files – Many languages use include files, and this is usually done at the top of the
program code. Include files contain some information that the program needs to know in order
to run the code contained in the program. Instead of copying all the code into the program
(which can take up space and get complex), the compiler will look for the instructions on how
to execute the item in the include files as well as the code you have written.
What standard programming languages are out there?
administrator Common Programming Questions
If you want to create programs that are executable on your computer, the languages below
will apply.
As to what language to use, unfortunately the answer isn’t usually clear cut. Its kind of like
asking what you would like to major in in college. If you already know exactly what you want
to do and why, you can work your way to an answer. If you don’t know exactly what you want
to do and why, there may be some experimenting involved.
Unless you have a specific need to use another language, I would recommend starting only with
one of the below four languages:
Visual Basic – If don’t mind limiting your applications to windows, and you want to create
useful tools that will be relatively small scale, and you want something you can learn quickly
and easily, Visual Basic is a great place to start.
C – If you are concerned about using your programs on operating systems other than windows,
want a language that is very popular and well supported, and want to learn a more powerful
programming language, C is a good place to start. C is a very powerful function based language
that has been around for years. It is well supported, well documented and still in wide use today.
C++ – If you want to learn a very powerful and cross platform language that is the standard in
large scale program creation today, C++ would be a good choice. C++ is an “object oriented”
programming language, which is considered the new paradigm in languages (as opposed to a
function based language like C). C++ can be used on a functional basis, and supports a lot of C
code as well.
Java – If you want your programs to be internet based, or if you know you want your programs
to run on multiple platforms, and/or you want to know what all the fuss is about, Java may be
your best choice in language. Java may also be your best choice if you want to learn a more
complex language and you will be the only one using your applications. We say that because in
order to run your applications a user with need the java runtime software installed on their
machine, and not all users will have it installed and/or know how to do so easily. There are
pluses and minuses to starting here as a beginner. It isn’t as easy to create visual based windows
programs as other programming languages. It doesn’t actually create executables, which is
counter-intuitive for new programmer and most users. It does have it’s benefits though, as it is
object oriented like C++ but it avoid some common traps that are likely to be difficult for
beginners. Java is thought by some to be the wave of the future and is often taught by schools
these days as the primary language of use, but VB, C and C++ are also widely used today.
Other languages you will hear mentioned often:
COBOL – Common Business Oriented Language – is primarily used in big business
applications that are data and text/number heavy. It is has been around for a long time and is
still widely used, but short of wanting to learn it to get a specific job we don’t recommend it for
beginning programmers.
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C# - “C Sharp” is Microsoft's attempted answer to Java. It is relatively new, somewhat based on
C/C++ and tries to incorporate some of the same internet functionality as Java without being
cross-platform. We don’t recommend this language for beginners, as it is not in widespread use
at this point and is limited only to Microsoft operating systems.
Pascal – Pascal was designed as a language to teach good programming skills, as it requires a
very disciplined approach when writing the code. Pascal is not considered as strong or powerful
a language as C, C++ or Java. It is still in use today, but it not recommended for the pure
beginner simply because the other languages mentioned are more supported and commonly
used.
What languages do I want to use for Web programming?
HTML – Hyper Text Markup Language – This is the standard language for web browsers to
interpret information from the internet. All the formatting of text, pictures, colors, backgrounds,
link creation, etc. is done in HTML. HTML is not very difficult to learn, and in fact there are
many programs available that will do a lot of the coding behind the scenes for you. If you just
want to create basic webpages, this is the route you will want to go.
PHP – PHP stands for “PHP Hypertext Pre-processor” – notice the first P actually stands for
PHP in the acronym, a little technique some creators like to use when naming their programs.
PHP is a more advanced language for web display, and allows you to use variables as well as
hide your code from the outside world. PHP also allows you to connect to databases in your
webpages, allowing for more complex and interactive content than HTML.
MySQL – though not a web programming language, MySQL is a database programming
language that is often used in conjunction with PHP to post web content. MySQL is a free for
the personal user, and uses commands that actually seem logical when creating and accessing
content. If you are going to create a webpage that needs a database for content (you may not
know you need one, but depending on what you want to do you might), you are likely going to
use MySQL on your webserver.
Glossary of common terms you will encounter as you learn programming:
administrator Common Programming Questions
Also see the "What do I need to know no matter what language I use?" section!
Compiler – A compiler is a program that reads the program you have written (the "code") and
translates it according to the language specs into an executable program.
Databse – A database is a file that holds information in a structured way, in some respects
similiar to a spreadsheet. They are often used in programming to store data and to retrieve that
data back for use by the program.
Algorithm – An algorithm is a set of instructions or steps used to solve a problem. If someone
asked you how to do something, and you told them to "do this, then this, then this, and if you
see this do this" you have just given them an algorithm. Programs use algorithms to get results
based on data.
Object Oriented – Object Oriented Programming (OOP) is a recent trend in programming
languages. OOP is a redesign of how programmers think about solving problems - instead of
using a function and algortihm approach, you think of the "objects" in the program and what
they need to do. Don't worry too much about OOP concepts as a beginner. When it is time for
you to learn them it will be obvious, and in some cases you may never have to.
Platform – Platform refers to the type of hardware and Operating System you are creating
software for. For example, Intel and Windows, or Mac and Mac OS.
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What do I need to know to create useful programs?
administrator Common Programming Questions
First you need to know whether you want to create programs that run on your (or some other)
computer, or if you want to write web pages that either just display information or have some
functionality involved. If you don’t really know yet, do not worry! The information on this site
will give you a good background to figure out where you want to go.
You will find that most books and websites you encounter on programming generally show you
text programs. This style of programming goes back to the days of prompt-based computing.
Some of you may remember using DOS or perhaps a VAX system in school, where you had to
enter commands on a command line (“c:\>”) to get things done. Since most programming
languages were written when command line interface was the primary interface, many of the
instructional manuals you will find use this method of teaching. You are probably much more
interested in creating windows based programs, those that run in an open window in your
current operating system. The windows and tools commonly used in the windows (menus, help
files, open and save files, etc) are found in what is called an Integrated Development
Environment (IDE). These environments provide the tools you can drag and drop into your
programs so you don’t have to write these types of tool from scratch - a very useful innovation.
Given that most teaching texts stress the command line interface, this can be confusing for the
person who is trying to learn and understand programming. You probably aren’t interested in
writing command line interface programs, yet that is most of what is being taught. Rest assured,
there are ways to easily write windows applications. Visual Basic is built to write Windows
applications specifically. Languages like C and C++ weren’t designed for Windows specifically,
but using IDE tools like Microsoft Visual C++ and Borland C++ Builder you can adapt your
knowledge to Windows based programs.
If you wish to create webpages or programs that function on the web, you have a few roads you
can choose. If you would just like to create webpages with text and graphical content, HTML is
probably the best choice for you. If you want to create more interactive pages or pages with
more advanced content, learning PHP and MySQL may be appropriate depending on what
exactly it is you want to do. If you want to create rather advanced programs that use the internet
to function, the more complex uses of Java may be what you are looking for.
How do I create a webpage and put it on the internet?
administrator Common Programming Questions
Your first step will be to design the content you want – text, graphics, number of pages, etc.
Once you do so, you can use an HTML editor (or a text editor for PHP/MySQL, etc.) to format
the content the way you would like. Easy enough, right?
Your next step will be to figure out how you want the page hosted. If you have an aol account,
they provide free webspace under an address like members.aol.com\yourscreenname\ and you
can post your pages there. If you don’t have aol, other hosts like geocities or tripod might offer
free webspace, but understand that they will probably put advertising and/or popups on your
site. When you get a free web host, you really get what you pay for. You can register your own
domain name (like www.mywebspace.com) for about $15 per year and set up hosting for that
domain with a web host using packages that start at about $5 per month. Be aware that the
process varies per web host, so read their instructions carefully. Keep in mind that all hosts will
support HTML, but if you want to use PHP or MySQL you will want to make sure the package
you are buying supports what you want to use. This will usually be clearly listed in the package
specs, and usually you will have to get the second package up (as opposed to the cheapest
package) to get MySQL support.
Once you have purchased your package, your web host will give instructions on how to upload
a page. If you purchased web hosting you will want to find a free FTP program to use to easily
transfer files, Core FTP is one freeware/shareware program that is easy to configure and use, but
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there are many others. The web host will give guidance on how to configure the FTP client and
send the pages to their server to be seen by the world.
Database creation – if you are going to be using MySQL for database access, you will need to
create and set up the database for use. Your web host will provide instructions on how to create
the database on their server, and you can connect to the database and create tables on it using
PHP scripts.
What is a Content Management System?
administrator Content Management Systems
Content Management Systems (CMS) are programs built to make building and managing web
content easy. They are programs built to make it easier to create and manage web sites, as
opposed to writing and changing the html and php code. CMS usually use a mySQP database on
the back end to store the data (text, images, organizational information) that gets displayed on
your website, and use the functions contained within the code to display that data in a way you
would like. CMS have a back end administrator login and menu so the creator and designer can
go in and both change the visual setup (often called “look and feel”) of the website as well as
interfaces to add new content to the website.
CMS offer many advantages over creating a website from scratch. The menus and organization
of your content, once initially designed, are handled by the CMS. In other words, when you add
new content the CMS takes care of helping users get there – as opposed to changing your menu
systems and internal links each time you add content to your website. Also, many of the design
functions are handled in templates that allow you to just install and begin creating content, as
opposed to spending a lot of time creating a look and formatting everything the way you would
like.
Depending on the CMS you choose, there are usually plenty of templates out on the internet free
to download that will allow you to get the type of look you are looking for. Two popular and
easy to use CMS are WordPress and Joomla. WordPress is often referred to as blog software,
but it has many CMS features as well and has a very easy and intuitive user interface. You can
post material to your website and arrange it by topic, date, subtopics, etc. These can be changed
after the initial setup, allowing you to change the design and flow of your site as it grows, or as
your ideas for the site change. Joomla is a more in depth CMS (and is the one used to design
this site). Joomla has many of the same features as WordPress, but has many more functions to
add various modules that allow more functions to be built into the site. Things like user
registration, poll taking, link structure, and new article appearance are all handled by Joomla –
allowing you to focus on creating material for your site once you have Joomla set up to your
satisfaction. Joomla is ultimately more complex and takes more time to learn than WordPress,
but once you master the various “ins and outs” of Joomla you will find more robust capabilities.
Get Started!
administrator Beginning Programming Tutorials
C++ is a very common programming language, and a good language to start learning basic
concepts with. I'm not going to say that it is the best language for a new programmer to try to
master. If you asked 10 different programmers that question, you'd likely get 5 different
answers. Usually, people reccomend whatever they find most useful. That's what I want you to
do - figure out what you find most useful. To do that, you will have to try different
programming languages over time and see which ones fit best for you - which language
structure makes sense, which one seems to be able to accomplish the goals you want, etc.
We are going to start demonstrating programming concepts using C++ because it is easy to
install, easy to write some basic programs in, has an easy to use Borland compiler, and the
output will make sense to Windows users (you get an .exe file) and Linux users (an executable
file will be created).
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Ok, now that that is out of the way, let's start by installing the C++ compiler! Once you have the
compiler working, we will go ahead and walk through some test programs to work on concepts!
For Windows users:
Go to http://cc.codegear.com/Free.aspx?id=24778 and download the free C++ compiler. Install
the .exe and let it install to the default directory (C:\Borland\CPP55\). The article found at
http://dn.codegear.com/article/21205 will help you set up your system properly - you will need
to make the path changes and the add the .cfg files.
You can use their instructions to test the compiler as well.
For Linux users:
Many distributions come with the G++ (yes, it is called G++ and not C++) compiler installed. If
not, use your package manager to install it.
What is a spreadsheet?
administrator Spreadsheets
A spreadsheet - in the most basic sense - is a grid that contains data. The current convention is
for spreadsheets to have numbered rows and lettered columns.
While spreadsheets may seem intimidating upon first look, they really are easy to learn.
One of the most useful elements of spreadsheets is that they are as "small" or as "big" as you
like. When you start up a new spreadsheet workbook, you see a huge number of cells, yet it is
possible to use only a few cells to create something useful to you. Don't be inimidated by the
initial size of the screen - think about what it is you are trying to do and how much space you
will need to do just that!
As you develop your knowledge of spreadsheets, you will find them useful tools for storing
lists, sorting alphabetical data, sorting numerical data, performing calculations on numerical
data, and modifying text. If you don't know why you would want to do some of those things yet,
do not worry - you may never have a need to do any of those things. As mentioned earlier,
spreadsheets are wonderful in that you don't have to use all the space and/or functionality they
have available - you only have to use them to do what you need to do! The key is in finding out
what spreadsheets CAN do, and how that can be useful to you!
What spreadsheet program should I use?
administrator Spreadsheets
Microsoft Excel is the industry standard - if you have that, you are all set in regards to this
question!
If you don't have a spreadsheet program, there are a few options available to you: You can
download one of the free spreadsheet programs available (OpenOffice Calc and Gnumeric are
good free spreadsheets) or use the Google Docs spreadsheet program online. I would
recommend downloading either OpenOffice Calc or Gnumeric, as those programs are faster
than Google Docs and the interface on Google Docs is a quite a bit different than Excel.
I find Google Docs a good place to store small spreadsheets, but if I'm going to do some actual
work on a spreadsheet I am doing it in Excel (or Gnumeric or OpenOffice Calc, both of which I
use at times). Also, most jobs you might be in and/or classes you might take will be using Excel,
so it is better to learn on the industry standard or something close to it. In my opinion, Gnumeric
or OpenOffice are fine to learn on - the basic formulas are all the same, and if you are reading
this you are a long way from using the more advanced Excel options at this point. Once you are
comfortable with one of the free options, when you have to transition to Excel it will be pretty
easy to do.
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Spreadsheet Tutorial 1 - A simple budget
administrator Spreadsheets
We are going to use a simple home budget as a tutorial. This is not meant to be an exhaustive
home budget, but a basic start to a budget to demonstrate some spreadsheet features.
Open a new spreadsheet and save it as "tutorial spreadsheet 1".
For the below cells in column A, enter the exact text I am telling you to enter, not the amount
those might be (that is coming next).
Enter the following in cell A1: Monthly Budget
Note: cell A1 refers to column A row 1. This is the top left cell on the spreadsheet, right under
the A and to the right of 1. If this doesn't make sense to you yet, it will become clearer to you as
you work with spreadsheets more. Eventually, it will become second nature to you!
In Cell A3 (skip cell A2): Monthly Income
A5: Expenses
A6: Rent
A7: Electric
A8: Heat (Gas/Oil)
A9: Cable
A10: Car Insurance
A11: Car Payment
A12: Gas
A13: Phone
A14: Cell Phone
A15: Total Expenses
Skip A16
A17: Net Per Month
Move the mouse pointer until you are on the line that is in the gray areas between the column
headers A and B. Your cursor should change into a line with two arrows pointing left and right.
If you click and hold the mouse down, you can resize the column by moving the mouse. In this
case, I would like you to double click on that line - it will automatically resize the column to the
largest element in the column to the left, in this case column A.
Now, we are going to enter some numerical data in column B. Some of this will seem obvious,
but I'll spell out each item.
In Cell B3: Enter your total monthly income. For Example "1,800" - without the quotes - would
be a legitimate entry. Don't enter "1800/mo" or anything else with text - we only want numbers
in column B!
Skip B4 and B5
B6: Enter your monthly rent
B7: Enter your monthly electric bill
B8: Enter your monthly bill for heating
B9: Enter your monthly cable bill
B10: Enter your monthly car insurance bill
B11: Enter your monthly car payment
B12: Enter your monthly bill for gas for your car
B13: Enter your monthly phone bill
B14: Enter your monthly cell phone bill
Skip B15, B16 and B17 for now
Ok, now we have our basic data in the spreadsheet - let's do some calculations!
In cell B15 type in (without the quotes) "=sum(B6:B14)". Note that the letters aren't case
sensitive, you could enter "=sum(b6:b14)" or "=SUM(B6:b14)" and it will work the same. Once
you type in the second parenthesis, hit Enter. B15 should now display the total of your monthly
expenses. Congratulations, you have completed your first spreadsheet formula!
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In cell B17 type in "=B3-B15". Cell B17 should now display the difference between your
income and expenses. Hopefully, this number is positive!
Notice now you can go back and change your income or expenses, and the calculated totals will
change automatically - this is one of the many powerful features of spreadsheets! Once you
design your data and calculations, you can change your data and see the results instantly!
