Abend, this is the short form of “abnormal end”. This abend is an unexpected or abnormal end of a process. If I talk about computer software, software crashes when a program stops unexpectedly.
For example, an error can freeze or crash in the code of a program when it is running one of the commands. The result is an unexpected (mostly inconsequential) end of the running program.
This term “abend” was first used in IBM OS / 360 system based on an error message. But now it is used by Novell Network Systems, and together it has also become a common programming term.