de and defensive linemen same thing a dt is also a defensive lineman both important depending upon what defensive scheme u use 4-3 or 3-4 in a 3-4 a dt is most crucial if your team is better rushing...
a defensive lineman is the person who basically tackles anyone who trys to tackle the person in possesion of the ball: ) this probalbly doesn't help at all...heck i guessed on this, sorry...oh well :...
A defensive ends job is to contain the outside for running backs, or pressuring the quarterback. A defensive tackles job is plow through the offensive line and sack the quarterback.
I play at a high school level as a freshman and am 200 pounds 6 foot 4 inches. The average defensive lineman in NFL or College should be about 260-300 pounds 6 foot 2 inches to 6 foot 10 inches.