From HomoExcelsior

1. Archaic: A copy of the data stored in the core memory of a computer, usually on a device for external storage.

2. Unix: A copy of the memory image of a program, usually dumped to disk after the process (program) received a signal or exception which it did not (or could not) catch. The core dump will generally include the code, stack, and data portions of the program image as of the moment of the dump and is often used by debuggers for post-mortem analysis.

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