Jiffy is an informal term for an undefined, short period of time and originated from the English expression jiffy (pronouns), for example, in "I'll be back in a jiffy".
The term has been taken over by computer engineers to indicate a very short time, usually the time of a clock wrench of the clock that controls the computer.
Early computer systems like the Commodore 64 and many game consoles using a television as a display screen synchronize their time interrupt with the vertical frequency of the television standard. 59.94 Hz for NTSC systems and 50.0 Hz for PAL systems.
In Linux systems on the i386 platform, since version 2.6.13, a jiffy is 4 milliseconds or 1/250 of a second. A jiffy on other Linux versions or other hardware may be different, usually between 1 ms and 10 ms.
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