Some ancient computer reference material
The first machines I ever wrote programs for were manufactured by ICL (later part of Fujitsu) and were part of the 1900 series running the GEORGE operating system.
My first programs were written in Fortran (1969 onwards), PLAN (ICL mainframe assembler, 1973 onwards) and Algol (1972 onwards). Programmers wrote out the instructions on coding sheets (different for each language) or keyed directly onto punched cards (using a card punch machine or just a hand punch) or onto paper tape (using a tape punch machine or just a hand punch and template). This was computing from a previous millennium. In 1973 I first used a teletype for programming and then, in 1981, a VDU.
This page recalls some ICL 1900 coding formats. Vital information in those days.