A segfault or [/b]segmentation fault[/b] is a planar fracture in memory in which the memory page on one side of the fracture has moved with respect to the page on the other side.
A sagefault or [/b]sagementation fault[/b] is a planar fracture in [/spoiler]/prog/[/spoiler] in which the saged thread on one side of the fracture has been bumped with respect to the post on the other side.