If we're talking about auto pistols tap rack bang is the way to go if we're talking about a jam.
If tap rack bang doesn't fix it then drop the mag and rack the slide repeatedly till the gun is clear. The gun can then be reloaded as usual.
There is a video of Clint Smith which someone posted in tactics and training last week that is very good with two exceptions.
http://www.youtube.com/watch?v=BfyULpEhmug&feature=player_detailpage#t=5s
The first exception is a hangfire or misfire.
If you experience a hang fire keep it pointed downrange for 30 seconds then eject the round.
The second exception is a squib.
If you think you've experienced a squib keep it pointed downrange for 30 seconds then drop the mag and rack the slide clearing the chamber.
Once you're sure the gun is unloaded then and only then check to make sure that there is no obstruction in the barrel.
The reason I'm bringing up a squib is that I experienced one several weeks ago.
I was wearing both earplugs and muffs and the gun went click on what I thought was the last round of the mag.
I simply thought that I may have had my hand in the way of the slide release and it didn't hold the slide back.
I inserted a new magazine and the gun failed to go into battery. Tap, Rack, the gun still didn't go into battery. Tap, Rack and again FTRTB.
I noticed that the bullets I was removing were set back a bit so I thought that I screwed up while reloading so I brought out another box that were made on a different press and with same results.
I finally brought the gun back to the safety table and disassembled it which is when I found the bullet lodged in the barrel.
The back of the bullet was black from the primer which made it very difficult to see.
Needless to say I had my guardian angel looking out for me that day.
Unless you're in a firefight fighting for your life there is no reason not to take a few seconds to ensure that there is no obstruction.