It's a ZX Machines Emulator for UNIX based operating systems (and Windows), including all the Sinclair computers:

• MK14
• ZX80
• ZX81
• ZX Spectrum
• QL
• Z88

And also:

• Microdigital TK80, TK82, TK82C, TK83, TK85, TK90X (Portuguese and Spanish), TK95 (Portuguese and Spanish)
• Timex Sinclair 1000, 1500, 2068
• Timex Computer 2048, 2068
• Inves Spectrum +
• Sam Coupe
• Pentagon
• Chloe 140 SE, 280 SE
• Chrome
• Prism
• ZX-Uno
• ZX-Evolution BaseConf (beta)
• ZX-Evolution TS-Conf
• ZX Spectrum Next
• Jupiter Ace
• Amstrad CPC 464, CPC 4128, CPC 664, CPC 6128
• Amstrad PCW 8256, PCW 8512
• MSX1
• Spectravideo 318/328
• Colecovision
• Sega SG1000
• Sega Master System