| Java | A programming language similar in syntax to C++ but compiles to a cross-platform bytecode. |
| JPEG | Joint Photographic Experts Group has defined a compression-decompression standard for colour and greyscale image applications. |
| JPEG (Joint Photographic Expert Group) | Scanners. An image compression/decompression standard that divides the image area into cells to condense information based on content analysis.
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| Jukebox | A device that allows a large number of optical discs to be held near-line. It consists of disc racks with space for one or more disc drives and robotic pick-and-place mechanisms. The robotic mechanism relieves the specified disc from the rack, loads it, correctly oriented, into a disc drive and/or returns the last disc read to the storage rack position. |