What is an elliptical machine? An elliptical machine is basically a kind of exercise machine that is designed to let you walk or run without causing joint problems. It has the same exercise value, but the pressure is distributed in a way that won't cause you long term issues (for many people with knee problems or with other injuries, this is a must). The main point of one is to burn calories - they're great for cardio, but because of the unique pressure distribution you won't be building much muscle from it. Elliptical Machines Guide goes through a bunch of different brands, and will let you know the pros and cons of each different one.