The Sinclair ZX Spectrum was launched in the 80’s at the same sort of time as the Commodore VIC-20 and BBC Model B Micros.
It was quite popular in Europe, largely because of Sir Clive’s marketing and European base. The original ZX Spectrum featured a 16 kb RAM and a 48 kb RAM variant.
The Spectrum series had a Keyboard Map from hell, with some keys having as many as FIVE different functions. You couldn’t enter the basic keywoards by typing them in, instead you had to find the key that corresponded to the command you needed, so for example pressing “J” for “LOAD”.