Defensive fronts
Defensive line techniques (0 to 9)
The 0 through 9 numbering that describes where a lineman lines up, from a 0-technique nose over the center to a 9-technique out past the tight end.
Technique numbers describe alignment, not ability. A 0-technique is head-up on the center; a 1-technique is on his shoulder; a 3-technique sits on the outside shoulder of the guard; a 5-technique is on the outside shoulder of the tackle; a 9-technique aligns outside the tight end.
Even numbers are head-up alignments and odd numbers are shaded to a shoulder. Knowing the number tells you the gap a lineman is responsible for and the block he is about to see.