What does the GEGL Operation in GIMP do?

Question

I see it under the Tools menu, but I've never used it before. What's it do?

Answer 1

It uses GEGL for an experimental operation - GEGL was supposed to replace GIMP's core image handler in 2000, but it only proved stable in ~2006.

This is mainly for developers I believe, as GEGL is still considered experimental.