Altair BASIC

Altair BASIC. It was the first commercially successful product for the nascent Microsoft company and a pivotal piece of software for the early microcomputer revolution. Developed by Bill Gates and Paul Allen with help from Monte Davidoff, this BASIC interpreter made the Altair 8800 computer accessible to hobbyists and programmers. Its creation and marketing established foundational business practices for the software industry and catalyzed the growth of personal computing.

History and development

The project began in late 1974 after Paul Allen saw the Altair 8800 on the cover of Popular Electronics. He convinced Bill Gates, then a student at Harvard University, to collaborate on a BASIC interpreter for the new machine, which used an Intel 8080 microprocessor. Without access to an actual Altair, they developed the software using a simulator written for a PDP-10 minicomputer at Harvard University. Monte Davidoff, another Harvard student, was recruited to write critical floating-point math routines. The completed interpreter was delivered to MITS, the manufacturer of the Altair, in March 1975, famously running correctly on the first attempt during a demonstration in Albuquerque, New Mexico.

Features and technical specifications

Written in Intel 8080 assembly language, Altair BASIC was designed to run in the minimal memory configuration of the early Altair 8800, which often had only 4 KB of RAM. It supported standard BASIC programming constructs, including GOTO statements, FOR...NEXT loops, and IF...THEN conditional branches. The interpreter provided direct access to the machine's hardware through PEEK and POKE commands and included support for single-precision floating-point arithmetic. It was distributed on paper tape and later on cassette tape, with different versions, such as 4K and 8K BASIC, offered based on the user's memory capacity.

Impact and legacy

The release of Altair BASIC is widely considered a landmark event that helped launch the microcomputer industry. It demonstrated that high-level language software could make complex hardware usable for a broad audience, inspiring a generation of hobbyists and entrepreneurs. The software's success provided the initial capital and credibility for Microsoft, enabling its subsequent deals with companies like Commodore International and Apple Inc.. Furthermore, the controversy surrounding its early unauthorized copying led to Bill Gates's famous "Open Letter to Hobbyists," which argued for the value of paid software and shaped early debates about software piracy and intellectual property.

Licensing and distribution

Initially, Altair BASIC was licensed exclusively to MITS on a royalty basis as part of a bundle with the Altair 8800 hardware. The original agreement granted Microsoft a fixed fee per copy sold. This distribution model was soon challenged by widespread copying among members of homebrew computer clubs. In 1976, Microsoft successfully renegotiated its contract with MITS to regain the rights to license the interpreter to other hardware manufacturers. This move allowed the company to market versions of BASIC for emerging systems from Radio Shack, Commodore International, and others, establishing a core revenue stream.

Relationship with Microsoft

Altair BASIC was the foundational product for Microsoft, then known as Micro-Soft. Its development proved the technical and business acumen of its founders, Bill Gates and Paul Allen. The revenue and industry relationships forged through its licensing were critical to the company's survival and early growth. The interpreter's codebase evolved into Microsoft BASIC, which became a near-ubiquitous component of early personal computers like the Apple II and the IBM PC. This product line cemented Microsoft's reputation as a leading supplier of programming languages and was a direct precursor to its later dominance in operating system software with MS-DOS and Microsoft Windows.

Category:BASIC interpreters Category:Microsoft software Category:1975 software