the ohmmeter is a very good in expensive piece of equipment to own i have about four different kinds, you can buy the cheapest one at any electronic store, radio shack carry a wide variety, the ohmmeter can be used to detect an open circuit, it is also use to check resistance and ac/dc voltage--the average person will only need to check for an open circuit and ac voltage.

there are two basic kinds of meters--analog--this meter has a needle that moves from left to right when you use the knob to set it on its desired setting--

the digital dosen't carry a needle instead it gives a digital reading and is usually more accurate.