Carry on Luggage
You should check with your airline first, but most domestic airlines permit a carry-on piece of luggage that is 45 linear (total) inches. A common sized bag for carry-on luggage is 22"x 14"x 9". Most airlines have a carry-on weight limit of 40 pounds.
Checked Luggage
Most airlines will allow you to check one bag and have one carry-on bag. There is normally a maximum weight limit of 50 pounds per checked bag as well as a size restriction. The most common maximum size bag allowed is 62 linear (total) inches. A common size bag for checking through is: 27" x 21" x 14".