Programming Windows: Microsoft Basic (Premium)

Today, Microsoft is most closely identified by its Redmond, Washington campus and the market dominance of Windows. But it started more humbly, in a strip mall office in a rundown part of Albuquerque, New Mexico and with its first home-grown version of the BASIC programming language.

I don’t want to get too bogged down in this pre-Windows ancient history. But the short version is that Bill Gates and Paul Allen founded Microsoft in 1975 specifically to sell BASIC for the first personal computer, called the MITS Altair 8800. Sold as a kit to enthusiasts---Gates and Allen had found out about it in Popular Electronics magazine in December 1974---the Altair was powered by an 8-bit 8080 processor. Gates and Allen knew it was powerful enough to run the BASIC programming language, and given their past successes building an emulator for the Intel 8008---the 8080’s predecessor---and various software development tools on a PDP-10 mainframe for their first company, called Traf-O-Data, they modified it for the newer chip and got to work.

Right. What’s BASIC?

BASIC had been created in 1964 by John G. Kemeny and Thomas E. Kurtz, two educators at Dartmouth College who wanted a programming language that was simple enough for non-engineers and scientists to use. After considering Fortran and ALGOL, Kemeny started work on his own simplified language, which he called BASIC, an acronym for Beginner's All-purpose Symbolic Instruction Code. It was based on Fortran, and it featured line numbers with one command per line.

Though it went on to legitimatize the Altair, BASIC was seen as a “toy language” by computer scientists. Most early implementations took the form of an interpreter, a software program that evaluated BASIC source code and then spit out the results, instead of a compiler. That is, a BASIC interpreter didn’t compile and link source code into a native, standalone application like C.

But that suited Gates and Allen just fine, as BASIC would fit better in the memory- and resource-constrained early computers than would more powerful and complex languages: Their Altair BASIC would require only 6 KB of RAM and it even included its own I/O system and line editor in addition to the interpreter. (That said, an entry-level Altair could be built with just 256 bytes of RAM.) BASIC was also easy to use, and in a world in which there was literally no software, being able to create your own applications was life-changing. For early personal computer makers, it was a requirement.

That’s the why of both Microsoft, as a company, and of the early personal computer revolution. The firm’s subsequent successes were based entirely on the rapid expansion of the market, over time, to include many, many more personal computers. And to expanding Microsoft’s offerings to include more programming languages and environments and then eventually productivity applications as well.

But before any of that could happen, Gates and Allen had to win ...