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Old-time hackers sometimes get nostalgic for blinkenlights because they were so much more fun to look at than a blank panel. Sadly, very few computers still have them (the three LEDs on a PC keyboard certainly don't count). The obvious reasons (cost of wiring, cost of front-panel cutouts, almost nobody needs or wants to interpret machine-register states on the fly anymore) are only part of the story. Another part of it is that radio-frequency leakage from the lamp wiring was beginning to be a problem as far back as transistor machines. But the most fundamental fact is that there are very few signals slow enough to blink an LED these days! With slow CPUs, you could watch the bus register or instruction counter tick, but at 33/66/150MHz it's all a blur.
blit /blit/ vt. 1. To copy a large array of bits from one part of a computer's memory to another part, particularly when the memory is being used to determine what is shown on a display screen. "The storage allocator picks through the table and copies the good parts up into high memory, and then blits it all back down again." See bitblt, BLT, dd, cat, blast, snarf. More generally, to perform some operation (such as toggling) on a large array of bits while moving them. 2. Sometimes all-capitalized as BLIT: an early experimental bit-mapped terminal designed by Rob Pike at Bell Labs, later commercialized as the AT&T 5620. (The folk etymology from 'Bell Labs Intelligent Terminal' is incorrect. Its creators liked to claim that "Blit" stood for the Bacon, Lettuce, and Interactive Tomato.)
blitter /blit'r/ n. A special-purpose chip or hardware system built to perform blit operations, esp. used for fast implementation of bit-mapped graphics. The Commodore Amiga and a few other micros have these, but sine 1990 the trend is away from them (however, see cycle of reincarnation). Syn. raster blaster.
blivet /bliv'U0259.gift/ n. [allegedly from a World War II military term meaning "ten pounds of manure in a five-pound bag"] 1. An intractable problem. 2. A crucial piece of hardware that can't be fixed or replaced if it breaks. 3. A tool that has been hacked over by so many incompetent programmers that it has become an unmaintainable tissue of hacks. 4. An out-of-control but unkillable development effort. 5. An embarrassing bug that pops up during a customer demo. 6. In the subjargon of computer security specialists, a denial-of-service attack performed by hogging limited resources that have no access controls (for example, shared spool space on a multi-user system).
This term has other meanings in other technical cultures; among experimental physicists and hardware engineers of various kinds it seems to mean

 
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