Applesoft BASIC tokenized file
Applesoft BASIC was licensed from Microsoft and originally made available to be loaded from tape or disk. Apple models starting with the Apple II+ (the first new model after the Apple II) had Applesoft BASIC in ROM instead of the older Integer BASIC. An Applesoft I language was first released in 1977, followed by Applesoft II Floating Point BASIC in 1978, which is the most-used version. The later Apple III BASIC was based on Applesoft.
Applesoft BASIC programs were stored in a tokenized format, in files which were designated in Apple DOS directories as type "A".
Similar to a number of other BASIC tokenizations (but distinct from Integer BASIC tokenization), Applesoft programs preserved ASCII characters unchanged in the 7-bit range (bytes with high bit clear) and used the "high bit set" byte values (#128-#155) to store tokens. BASIC lines were separated by the null byte (00), and started with a two-byte address of the next program line in memory, then a two-byte little-endian integer giving the line number, then the tokenized commands and literal characters of the program line.
