Debugging stATements inserted into a program thAT emit output or log indicATors of the program' s stATe to a file so you can see where it dies or pin down the cause of surprising behaviour. The term is probably a reference to the Hansel and Gretel story from the Brothers Grimm in several variants, a character leaves a trail of bread crumbs so as not to get lost in the woods. [Jargon File]