"Defensive Backs" vis-a-vis "Linebackers" in Football

[DonRocks]

Just as I have an intellectual void about soccer, some of us (including, to some degree, me) may have a similar void about football.

In case there is any confusion about the terms "linebacker" and "defensive back," they are not the same positions, at least not in any definition that I've ever heard.

The good news is that it's very easy to remember, just from the names:

A "linebacker" backs up the line. They are very strong, and play behind the defensive line to prevent escaping runners, and to defend against short passes (generally less than ten yards). During a blitz, they'll often come in to try and sack the quarterback.

A "defensive back" backs up the defense. They are mobile and quick, and play behind the entire defense to prevent the long pass, and as the final resort against breakaway runs - both "cornerbacks" and "safeties" are defensive backs.