(1) (
Critical
Path
Method) A project management planning and control technique. The critical path is the series of tasks that have no built-in slack time. Any one of those tasks that takes longer to complete lengthens the total project time.
(2) (
Cost
Per
Mille/
Milli - per thousand) CPM is typically the price paid for a banner ad on 1,000 Web pages. For example, a $25 CPM means the website owner is paid 2.5 cents per impression. More often, CPM is around $3, which equates to three tenths of a cent (.003) per impression. See
pay-per-click,
eCPM,
RPM and
banner ad.
(3) (
Copies
Per
Minute) The rated speed of a printer or copy machine.
(4) (CP/M) (
Control
Program for
Microprocessors) A single user operating system for the 8080 and Z80 microprocessors. Created by Gary Kildall of Digital Research, CP/M had its heyday in the early 1980s, and although unsophisticated, was a major contributor to the personal computer revolution. However, CP/M computer vendors never standardized a floppy disk or screen format, requiring software publishers to create and stock multiple CP/M versions. After entering this uncontrolled market in 1981, IBM readily set the personal computer standards with its PC, and some of those standards remain to this day (see
IBM PC).
CP/M Might Have Become DOS
Although IBM asked Kildall to provide the operating system for its new PC, he did not agree to IBM's demands. IBM went to Microsoft, which purchased QDOS from Seattle Computer Products and turned it into PC-DOS and MS-DOS. The rest is history. The irony is that Microsoft's DOS was modeled after CP/M. Digital Research was later acquired by Novell and then Caldera, which later merged with The SCO Group.
The Otrona Attache
Introduced in 1982, the Attache was the smallest CP/M portable computer on the market. Weighing 17 pounds and priced at $5,000, the Attache was an elite computer for prosperous families. (Image courtesy of Robin Bartlett.)
CP/M News Clips in Its Heyday
CP/M was the only OS that ran on microcomputers from different vendors. With a Z80 card, it even ran on the Apple II. A major contributor to the personal computer revolution, CP/M motivated IBM to create the PC; the most successful desktop platform in history.