Those computers are the 8-bit generation like the BBC Master Mirco, ZX Spectrum, Commodore 64 even the IBM PC powered by a Z80 Zilog CPU. Most 8-bit computers are refered as "Teletext machines" however time as evolved with 32-bit or 64-bit PCs like Windows NT series or newer operating systems. Hence those 8-bit computers are offically decleared - obsolete.