The Atari ST is a 68000 based graphical computer. It was often considered a "poor mans Macintosh clone", as it was considerably less expensive than Apple's offering, and clearly did borrow a few ideas from the Mac. user interface.
A couple of neat features of the ST are that it contains its OS in ROM, and that it reads and writes diskettes in DOS "FAT" format.
I have four Atari ST's in my collection, two early model 520STs with separate power supplies and floppy drives, a later model 520ST which has the power supply and floppy drive integrated, and a 1040ST which is essentially the same machine as the later 520 but with 1M of RAM instead of 512k.
One early model Atari 520ST was donated by C. Goffin, who has provided me with its history.
Click any photo to view a large high-resolution image.
Here we see a complete 520ST system. Clockwise from upper left:
520ST power supply, SF354 power supply, SM124 Monitor, SF354 Diskette Drive, Atari ST mouse. Atari 520ST computer.
This is an original Atari 520ST main unit, which has a separate power supply, and does not include an internal diskette drive. I have two of these, with the only apparent difference being that one of them has an optional TV output.
Closeup of the 520ST main unit / keyboard.
The 520ST rear panel. Left to right:
RESET switch, Power switch, Midi Out, Midi In, TV out & Channel selector (lower unit only), Monitor, Printer, Modem (serial), Floppy disk, Hard disk.
Left side view of the ST520. This is a cartridge slot for ROM based software.
Right side view of the 520ST. Left to right:
Mouse/Joystick (0), Joystick (1)
Information label on bottom of 520ST.
The Atari 1040ST main unit. Note the addition of the internal diskette drive. This model also incorporates an internal power supply.
Closeup of the 1040ST main unit / keyboard.
The 1040ST rear panel. Left to right:
Modem (serial), Printer, Hard disk, Floppy Disk, Monitor, Power switch, Power cord connector, RESET switch.
Left side view of 1040ST. Left to right:
Midi out, Midi in, Cartridge slot for ROM based software.
Right side view of 1040ST. This is the integrated 3.5" DS/DD disk drive which holds 720k (double the capacity of the 520's external drive). Note: On the 1040ST, the mouse and joystick plug into a slot in the bottom of the machine.
Information label on bottom of 1040ST.
This 520ST is a later edition, which was physically more like the 1040ST. Note the internal floppy diskette drive. This model also incorporates an internal power supply.
Rear view of the later edition 520ST. Note that this one has the optional RF (TV) output.
Left to right:
Modem (serial), Printer, Hard disk, Floppy Disk, TV output, Channel select, Monitor, Power switch, Power cord connector, RESET switch.
Front view of the SF354 floppy disk drive. This is a single-sided 3.5" drive holding 360k.
Rear view of the SF354 floppy disk drive. Left to right:
Data in (from computer), Data out (for daisy-chained devices), Power from external supply, Power switch.
Here are the 520ST and 1040ST owners manuals, as well as the manuals for the SF354 floppy disk drive and the SM124 monitor.
Here is the Atari Basic Sourcebook, and and original Atari language diskette.