The figure-of-eight is used mostly as a stopper knot, similar to the overhand. It is a little bulkier, so does a slightly better job in this regard.

If you can tie one of these, then you should also be able to tie the figure-of-eight on a bight, which is a very useful knot. It is also the starting point of the rethreaded figure-of-eight, so is important to know for that.

Note that in very flexible or thinner diameter rope, the knot will set slightly differently.

figure_8.jpg (21987 bytes)
Pass the end of the rope over itself... 125-2543_img.jpg (25612 bytes)
...and then back under itself. 125-2544_img.jpg (24805 bytes)
Feed the end of the rope down through the loop formed. 125-2545_img.jpg (25344 bytes)
Pull tight and set. Note the distinctive shape of the knot. 125-2546_img.jpg (22918 bytes)