 It includes keywords for Atari-specific features and lacks support for string arrays, for example.The language was originally an 8 KB ROM cartridge for the first machines in the 8-bit series, the 400, 800 and 1200XL.Starting with the 600XL and 800XL, BASIC was built-in to the machines, but can be disabled by holding down the codice_1 key while booting.