One commonly used software for the Sol-20 was the BASIC/5 language. This was able to run in even a minimal machine with a 4 KB expansion, but in order to fit it had only single-precision floating point numbers and lacked string variables. An Extended BASIC that ran in 8 KB added strings and other functions. Processor Technology also sold a wide variety of other programs, including many games, on cassette format for the Sol, or on punch tape for other S-100 machines.
