...Recording is done by pressing particular keyboard keys on the computer. The software then saves the sequence and timing of behaviours. Note that the DOS (1995: https://sourceforge.net/projects/expr/files/expr/fb-port-expr-00-1995/EXPR-binary-DOS-0.0.1995.tar.gz/download) version is currently the only fully functional and is recommended for use. On modern computers, DOS software can run in DOSBOX (https://www.dosbox.com/).