Assembly code was the step between the original way of programming computers to the modern way of programming. Originally, the huge hulks of electronics from the early days of computing, such as ENIAC and the Z1, were programmed by hooking up wires in a certain way to represent the "0"s and "1"s that computers understand. It was tedious and slow to program this way, but it was effective because the programs were often used for weeks at a time.

Computers eventually became more advanced, and several types of memory systems were built. To modify these manually would be nightmarish for a programmer! So, programming languages were developed. These were programs that turned the programmer's program into a form the computer could understand. The most basic of these was called assembly code.

Assembly code eventually gave way to high-level programming, with commands that were closer to normal english, and didn't crash the computer as easily. Today, most computer programs are written in high-level languages. However, some people still program graphing calculators and supercomputers. If you don't believe that calculators can be programmed, check out Texas Instruments graphing calculator webpage; or the TI programmer's webpage, ticalc.org.

The most common way of programming computers today is to use a high-level programming language. What's this mean? It means programming the computer using instructions that are easy for us humans to understand and remember. For example:

This is a simple program, written in the high-level language QBasic. The same program in C++ looks like this:

Basically, both programs clear the screen, display "Hello world!", and then quit.