history - in the beginning
1971 - what would become the Interex Contributed Software Library is born
1972 - the HP 3000 is born
1977 - first conference software swap tape is produced
1982 - last cumulative CSL tape; switch to "best of" + incremental
1988 - CSL switches to incremental-only format
1990 - CSL split into separate MPE and MPE/XL distributions