How to make your own computer program

Ah those magical computer programs... what would we do without them? Indeed, If we did not have software, then our PCs would be completely useless pieces of metal (and metalloid). Yet, where to theses programs come from? People need to create them, but who, and how?A common misconception is that only large corporations or geniuses can create computer software. This is completely false. Any average person has the intellectual capacity to do so, and it won't cost a dime!This is what I'm going to show you in this very article...

How do they work?

Before creating your own, you need to know how they work. A program, in computing, is simply a set ofstoredinstructionsthat the target computer can execute. These series of instructions, when executed in the processor, perform specific sets of tasks, as defined by the programmer. Interactive programs accomplish this in three tasks:

  • Inputis the collection of data needed by the program.
  • Calculationis the part of the program that manipulates theinput.
  • Outputis the end result ofcalculation.
Per example, if we were to make a calculator program,inputwould be when the user types in numbers,calculationwould be the actual execution of the mathematical operations andoutputwould be when the program displays the answer.

Creating you own:

Programs are created with what are called "programming languages". These are simply computer commands written in a syntax that humans can understand. Several types of languages exist, each serving a different purpose.Below is a list of three major types:

  • Scripts:These are the most simple types of programs. Scripts are sets of instructions that control one or morealready existingprogram. Good examples of scripts are batch files, visual basic for applications (VBA), CSS and JavaScript. To write a script, you'll first need to learn the commands and syntax of the scripting language you want to write in. I will not show these in this article because it would make it way too long.
  • Web applications:Web applications (or simply web "apps") are programs that are made accessible over the Internet through a browser-controlled environment. These programs, like scripts, are also created by writing instructions in files which are then analyzed by a program called "interpreter". Some of the most popular web programming languages include: PHP, ASP and of course... JAVA.
  • Executable files: Up until now, the programs that we've looked over need another program in order to execute! What a frustrating fact! OK, but here's where things get really interesting. Executable files (*.exe on Windows) run directly on the computer! These files are composed of extremely complex instructions, which are understood by the processor itself! Programs like Paint, Open Office, Mozilla Firefox, etc. are all executables. The only problem is, the codes contained in executable files are too complicated for us to write. This is why you must use a programming language to simplify the task. A programming language is simply a language which is translated into an executable with a program that is called a "compiler". Many great free ones exist: BASIC is a very easy one to learn, but it's quite limited. C++ is my personal favorite, but it is somewhat complicated. There's also Assembly, Haskell, PASCAL, FORTRAN, COBOL, C#, Eiffel, and the list goes on and on...

In Retrospect

Basically, all depends on what type of program you want to create. In each case, you'll need to learn how to use a different "language" and it's tools. Learning to program is a long and laborious task, but I recommend it to anybody willing to sacrifice a few hours of their time. Finally, I wish you the best of luck on your road to becoming a computer programmer.