[afandian]

The 'k' spelling is American. Look at the ports on the BBC and you'll find British spellings of 'analogue', 'disc'.

https://oldcomputers.net/bbc-micro.html

The User manual contains more language. For example, 'program' for computer program (vs 'programme' which would be used for TV)

http://bbc.nvg.org/doc/BBCUserGuide-1.00.pdf

[Doctor_Fegg]

The Amstrad CPC was "disc" too, reputedly because the first mouldings used it by mistake and Amstrad was too cheap to ever correct their error.