BASIC#
In computer programming, BASIC
(an acronym for Beginner's All-purpose Symbolic Instruction Code) is a family of high-level programming languages. The original BASIC was designed in 1964 by John George Kemeny and Thomas Eugene Kurtz at Dartmouth College in New Hampshire, USA to provide computer access to non-science students. Many versions of BASIC, with widely differing features and syntax, emerged during the 1960s and 70s.
The introduction of the Altair 8800 in 1975 led Gates and Allen to form Microsoft to make a BASIC interpreter for that platform. They were most familiar with BASIC PLUS from the PDP-11, and patterned their BASIC on that version. From that point on, Microsoft BASIC has been the standard by which all are measured.
The Atari 8-bit machines were originally games consoles, but switched to be home computers while they were being designed. This led to a need for BASIC on the platform. Atari licensed MS BASIC, but could not get it to fit into an 8kB ROM, which was all that was available at the time. They turned to Shepardson Microsystems, who produced Atari BASIC to fill this need. Atari BASIC had many differences from the MS BASICs of the era, and the Atari was always unique in this regard.
Atari BASIC was very slow, much slower than BASIC running on other home computers that were (otherwise) slower than the Atari. This led to a profusion of new BASICs for the platform, perhaps unlike any other 8-bit machine of the era. The release of TURBO-BASIC XL in 1985 was something like a bomb going off, largely replacing Atari BASIC wholescale. There was really nothing similar in the Commodore or Apple II markets, where there were lots of basics but most remained obscure.
Development continues; Altirra Basic, Basic++ and FastBasic were all written in the 2010s, and they will likely not be the last.
Basic versions for the Atari Computers in order of production year: