Teach me something

How do you outline a picture? (Like taking a picture with a dog in a background, and only outline the dog.)

Should be like under effects,
like glow or something.
I'm use to Gimp,
so not sure.

add glow ass he said..
select the dog
double click lair and ok...
outer glow or just select the dog or use lasso to go around it it select the dog
edit>stroke
chose like 2 pixels and ok.. it will outline it