A Technical History of Apple's Operating Systems - Mac OS X Internals

Mac OS X Internals (www.osxbook.com) 5
Figure 1–2 shows a test program entered at the monitor’s “backslash” prompt.
The first line of hexadecimal numbers is the program itself. Its purpose is to print a
continuous stream of ASCII characters on the display. Typing 0.A prints a listing of
the program, and typing R runs the program.
FIGURE 1–2 The Apple I’s firmware-resident system monitor
Compared to the UNIX general-purpose time-sharing system, which was in its
Sixth Edition then, the Apple I’s operating environment was decidedly puny. How-
ever, a contemporary computer system running UNIX would have cost many thou-
sands of dollars. The Apple I was an attempt to make computing affordable for hob-
byists, and as those behind it hoped, for the masses. Within the first nine months of
the Apple I’s introduction, all but a few of the two hundred or so units manufactured
had been sold.