The ABC-24 and ABC-26 could run up to 8 programs simultaneously and couls manage 7 workstations under M/PM (according to the advertisement). they had a real-time clock and 96 graphic symbols built-in.
There were several models : 20, 21, 22, 23, 24, 25 and 26, mostly differentiated by the storage capacities...
The 2x Models were the successors of the ABC 10, which had a digital tape auxillary memory, supplied with DOSKET-T.
AI DOSKET is the AI Electronics Operating System. A lot of languages were developed for these computers: MBasic, CBasic, Basic, Pascal, Cobol80, PL/3, Fortran IV and assembler.
Picture courtesy of Computer Modell Katalog.