Mainframes with which *I've* worked were driven with hole-punched cards (5081s they were called, as that was the "form number"). The cards had 80 columns, with 10 rows per column. I worked at an IBM office. The "mainframes" were Model 360/20s, and they were 6-feet tall by about 3-feet by about 8 feet. the operating system was loaded in the first tray of cards. The program (like, say, a payroll program) was the second tray of cards. The data (like, say, a bunch of employee names and hours served) was the third tray of cards. A tray of cards was these 5081s about three feet deep. The output was on a printer about 5 feet tall by 2 feet deep by 4 feet wide, on a continuous sheet of 14-inch by 11-inch papers.
The next model was Model 30, then 45, and so on...
Then there were mainframes more sophisticated that had the operating system stored on a disk!!! The disks were (are? - I haven't been around them for awhile) about 18-20 inches wide in a stack rotating rapidly as you might imagine. There were banks of them. Backups on tape drives about 6 feet tall, with reels of tape about a foot across. Operating systems named VM (Virtual Machine, of which I was System Programmer) and MVS (Multiple Virtual System).
VM is a user-interactive system, with command-line terminals, "Sherman Tank" size, multi-color text on a black background. The subsystem for user interaction was CMS, and included such elements as XEDIT (an editor) REXX (a scripting language) PROFS (an email system) compiled languages (COBOL, Fortran, various others)...
MVS is a "production" system with a "command-line" control. It runs submitted "jobs" or discrete instruction groups including a name, a named program, and a set of input and output statements to be used by the program. (Multiple sets of programs may be executed in "steps").
All the mainframes described above are IBM. Other companies make other sorts.
2007-02-28 04:46:34
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answer #1
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answered by fjpoblam 7
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