Complex sentence: "The Monkey" was a Macintosh application developed by Steve Capps prior to 1983; it used journaling hooks to feed random events into Mac programs, and was used to test for bugs in MacPaint.
Split into simpler sentences: The Monkey was a Macintosh application developed by Steve Capps prior to 1983. It used journaling hooks to feed random events into Mac programs, and was used to test for bugs in MacPaint.