un-junk mail

When I slide a message from the junk box to the inbox, does Mail recognize the sender so that next time it will go to inbox, or do I have to create a rule every time something accidentally goes to junk so that it will go to my inbox? I'm talking about messages that have no rue attached to them yet. By the way, I had to choose a random subject to post this, since "Mail" wasn't among the options.