How to make a text link "hot?"

I know this has been mentioned a million times in the forums but I can't seem to find an example at the moment. How again do we make links hot, aka clickable in either comments, posts, or signatures? I know there is something you need to add at either end of the link.

Thanks

See the Text Style Menu directly under the smilies below for the tags needed.

Thanks Jim, you're a rockstar!

I think it would be great if this info. could be placed in a more prominent place. I would never have thought to look there, and I've seen that a huge number of others can't find this info. either. "Text Style Menu" just doesn't make me think "links", even though there's plenty of other useful info. there too. It's just too bad people have to keep asking-- wastes time, space & energy & creates boredom. Just my humble opinion!

Jim and Kurt, if my signature now has a hot link in it, then I thank you both very much - I have been trying to work this out for a while now, on and off.