Microsoft has always held an important place in the world of personal computers. However, in this phase of its development, it was mainly as the company that provided something of a universal basic for the variety of computers to consumers at the time.
When Atari first released its line of home computers in the late 1970s, it created its own basic. Atari Basic has its particular share of quirks and compatibility issues and so they encouraged Microsoft to release its version of Basic for the Atari Computer. Unfortunately, the basic code cannot be compiled so, in order to share a program, the person who was running the program must also have a copy of Microsoft Basic.