Some of these answers are close and other are way off. Don’t mean to put anyone down. I just think that some of the answerers are a little confused about the question.

A chop saw refers to a saw used to cut metal. It has a fiberglass blade that has diamond dust embedded in it and cuts by friction.

A power miter saw is the saw carpenters use to cut wood. It is electric and can be set to cut straight across a piece of wood. It can also be adjusted to cut at an angle (usually up to 45 degrees)

To expand further, there is a second type of power miter saw. It is known as a Compound miter saw. It can not only cut across but has the added ability of being able to lean to the side allowing a compound angle to be cut.

Chop saw goes up and down and straight cut angles
Power mitre saw does those and also can turn the balde on an angle to achieve a complex cut

Gordon is close but he is reffering to a cut off saw

a chop saw uses a cutting wheel, kind of a grinding type wheel and is used for metal. A power miter uses a saw blade and is used for wood products

A chop saw has a blade mounted on the arm, and the arm will only cut straight down. It’s only good for simple cuts, or chopping through long pieces quickly. A miter saw can perform the same action as a chop saw, and then some. A miter saw can be set to cut at any angle you choose, they all have guides to assist in setting the angle. (great if you’re installing new trim in your home for example) A compound slide miter saw does these things, plus it accomodates wider pieces of wood because the arm slides forward and back.

1. Chop saw is for steel, saw pulls down like a miter saw does.
2.Miter saw is for wood and cuts miter joints such as 45s
3.Compound miter is same as number 2 but also rotates vertically right and left 45 degrees
4. Sliding miter saw works as number 2 plus works like a radial arm saw also. You can actually pull the blade toward yourself in addition to up & down allowing you to cut wider pieces of wood.

Ok the terms are used interchangebly. A chop saw for wood is what you see used when cutting, studs, trim, siding, etc. All chop saws now do up to a 45 degree miter and can be used for angled cuts. Their is no difference between the two terms.

A metal chop saw is diffent than a wood one. Just ask when you go to the store. Good brands are Bosch, Dewalt, Crastman, and Makita.

gordon is right. A chop saw is for metal and concrete materials. It uses a blade like a grinder blade. The miter saw is used for making precision cuts in trim, molding, and other pieces of wood and uses a saw blade with teeth.