A football safety is worth two points. Learn what causes one, how impetus separates a safety from a touchback, and what happens after the score.

A zone blitz sends pressure while playing zone coverage. Learn how the classic five-man fire zone works, why linemen drop, and how offenses beat it.

Cover 3 divides the deep field into three zones. Learn each defender's job, strengths, weaknesses, offensive answers and how to recognize it live.

Mesh pairs two shallow crossing routes to stress man and zone coverage. Learn the route spacing, quarterback reads, legal limits and defensive counters.

Illegal motion is a five-yard NFL penalty when an offensive player is moving illegally at the snap. Learn who may move, which directions are legal, and how the foul differs from an illegal shift or false start.

The Colts’ reported one-year agreement with Keenan Allen adds a proven third-down target to an injury-thinned receiver room. Here is what changes now.

The Giants’ reported Najee Harris signing adds real committee and goal-line risk for Cam Skattebo. Here’s the new draft range for both backs.

Roughing the kicker is a 15-yard penalty and automatic first down. Learn how it differs from running into the kicker and when contact is legal.

Za'Darius Smith gives Atlanta a proven rotational pass rusher after major edge losses. Here's what is confirmed, what changes and the biggest risk.

An illegal shift happens when multiple offensive players move before the snap and the offense fails to reset for one full second. Learn the five-yard NFL rule and how it differs from illegal motion and a false start.