There are several factors involved in selecting the best saw for a particular job: the material being cut, if you are cutting a curve or a straight line, how precise the cut should be, and how fast you woudl like to get the work done. The following is a brief overview of some of the common types of saws.
Hack saws have really small teeth that do not remove alot of material with each stroke. They can be useful for cutting hard materials such as metal or pipe.
Crosscut saw or box saw is the type most people think of when they think of a handsaw. It's ideal for cutting wood across teh grain.
Key-hole saws are useful for cutting small holes or curves in wood. Commonly used to cut holes in drywall for electrical boxes.
Table saws are used for cutting straight lines and angled cuts. Ideal for ripping straight segments of wood.
Jig saw rest on a flat metal foot and have a small, narrow blade that moves up and down rapidly to cut through wood.
Circular saws are powered by an electric motor with a round blade. Several types of blades can be used for ripping wood free hand or making crosscuts.
Reciprocating saw is similar to a jig saw but has smaller feet and typically more power. Ideal for cutting in tight spaces or doing demolition.
Miter saws are similar to circular saw held by an arm that allows for tilting and turning to cut compound miters.