Integer BASIC

Integer BASIC is a BASIC interpreter that Steve Wozniak wrote for the Apple I and the Apple II. It was first sold on cassette for the Apple I in 1976 and then placed in ROM on the Apple II when that machine shipped in 1977, which made it the first version of BASIC that many early home computer owners ever used. As the name says, its only numeric data type was the integer. Whole numbers were held in a compact 16-bit form that was quicker to process than the floating-point formats of most BASICs of the time, but the lack of fractions limited it as a general-purpose language. Strings were treated as arrays of characters, with substrings taken by slicing, a style that came from HP Time-Shared BASIC rather than from the DEC-derived Microsoft BASIC. Wozniak first called it GAME BASIC, and it was known simply as Apple BASIC on the Apple I. Apple phased it out in favor of Applesoft BASIC, a licensed port of Microsoft BASIC with floating-point support, beginning with the Apple II Plus in 1979.