What Is A Short Circuit?
A short circuit is a break in the normal path of an electrical current and results when a hot current comes into contact with either a neutral or ground current. The result is that your lamp, toaster or other "load" doesn't work; you'll also discover that you've blown a fuse or tripped a breaker at your breaker box.
Fixing The Problem
First eliminate the load (let's say it's a lamp) as the problem by plugging it into a different outlet that you know is working (preferably one fed by a different fuse or breaker switch). If the lamp works, you need to investigate further to isolate what caused the mishap.
Short Circuit or Overload?
How do you know if it's a short circuit or an overload? The easiest way is to turn off all switches and appliances fed by the blown or tripped circuit. If you're not sure, just turn off everything in the house. At your breaker box, reset the tripped breaker or replace the blown fuse. Turn on the lamp, plugged into the same outlet as before. If you blow a fuse or trip a breaker without turning anything else on, it is likely that you have a short in the system.
Turn off the power to the area at your breaker box (if you're not sure, turn off the main power switch). Remove the cover plate to the switch and/or to the outlet serving the lamp. Look for evidence of burned wire casing and the smell of charred plastic, loose wiring or other problem.
Tip: A burning smell could be faulty wiring should be replaced by an electrician.