Programming Languages

What Is A Program?

A program is a step-by-step set of instructions that controls the computer hardware. This may include complex sets of instructions that let you write, spell-check, and send an e-mail message; or it may be something simple like a program that tells you the current time in different time zone.

Here is an alternative view of what a program is:

 

When you create a program, you tell the computer what to do. Since the computer can't understand speech and since hitting it - no matter what emotional value that has for you - does little to the PC, your final line of communication is to write the computer a note-a file on disk.


Dan Gookin, C for Dummies, p.11

As you saw in a previous page programs are grouped into three types. Operating Systems like Linux or Windows, Programming Languages, and Applications like a word processor, a spreadsheet or your favourite game. Operating Systems run the computer and applications are designed for specific tasks such as accounting or graphic design, so ...

What are Programming Languages?

The main purpose of each different programming language is to translate the instructions of the person using the computer into a language the machine understands. Since all human languages are not accurate or careful enough for giving instructions to computers, and we cannot easily use the computer's own language, then people have invented simple but powerful languages to write these instructions. These are programming languages.

Some common programming languages are:

Basic
C (and C++)
Cobol
Fortran
Java
Perl

The Language of the Machine

The computer's language is little more than patterns of electrical current running through complex circuits. Engineers represent the on and off pulses of electricity that make up the machine's language with 1s and 0s. Therefore, a computer program written in machine language might look like this:

0010 1010 1010 1011 1101 1000 0011 1010 1100 1001 1000 1100 0110 1010 1000 1011 0101 0101 010 1111 0101 1010 1010 1000 1100 1100 1110 0011 1100 0011

The Art of Translating

Most programs that you use on a day to day basis are executable files that are stored on a hard drive or CD-ROM. When you double click an icon, the computer retrieves the executable file linked to the icon and loads it into memory then runs it. This is called executing the program.

For more details about some common computer languages, visit the Programming Languages page.