Let's start with some of the more non-traditional statistics.

    Expected Points Added (EPA) - A measure of value taking into account down, distance to go, and field position. Ensures that a gain of 7 yards on 2nd and 5 is given significantly more value than a gain of 7 yards on 2nd and 15.

    Offensive EPA (O. EPA) - EPA per play captured from the offensive side.
    0.1 is really good, and -0.1 is really bad.

    Defensive EPA (D. EPA) - Same as above, but captured from the defensive side.
    -0.1 is really good, and 0.1 is really bad.

    Offensive Success Rate (O. SR) - A measure of how often a team runs a "successful play." This is based on EPA, but can be simplified to gaining 6 yards on 1st and 10, and gaining a first down on 2nd down.
    >50% is really good. 40% is really bad.

    Defensive Success Rate (D. SR) - A measure of how often a team allows a "successful play."
    40% is really good. 50% is really bad.

    Win Probability (WP) - The percentage chance that a team will win the current game.

    Win Probability Added (WPA) - Quantifies the change in win probability based on a certain play. A sack-fumble in a close game would have a significantly higher WPA than a sack-fumble in a game where one team is up by 30.

    Luck - A measure by how many Wins a team over-performed or underperformed. A team with -2 luck was expected to win 2 more games than they actually did, based on fumble luck (recovering fumbles is very difficult to be "good" at), field goal expectation, and point differential.

    Adj. Pass% - A context-neutral look at how often a team passes, adjusted for the situation in the game. A team that is winning for the entire game would be less likely to throw the ball, whereas a losing team is much more likely to throw the ball.

    Explosiveness - When a play goes well, this measures how well. Teams that accrue big chunks of yardage will rank highly here. Low explosiveness is not necessarily bad. Trevor Harris offences have always been a low explosiveness group, but make up for it with an extremely high Success Rate.

    EPA Composite - A mixture of rushing EPA per play & passing EPA per play. Passing offence and defence tends to correlate more with winning, so it is given a higher weight.

    Depth of Throw / Target (DoT) - A measure of how far down the field a passer throws the ball, or how far down the field a receiver is initially targeted.

    Completion Percentage Over Expected (CPOE) - A measure of completion percentage after adjusting for how far a QB throws the ball down the field. A QB could have a great raw completion percentage if they only threw 3 yard passes, but this adjusts for depth of throw.

    Expected Catches (xC) - A measure of how many receptions a receiver should have had based on where their targets occurred. A receiver running 30 yard posts should have less xC in a game than a receiver running 5 yard digs.