Given the task definition and input, reply with output. In this task, we ask you to rewrite a sentence in simple English without changing its general meaning. Essentially, you want to make the sentence easier to read by using simpler words, utilizing more straightforward sentence structures, and omitting non-essential information etc.

In computing , a crash , or system crash , occurs when a computer program such as a software application or an operating system stops functioning properly and exits .
A Computer crash is when a computer program stops running normally .