Offensive plays

Offensive nomenclature
In the calling of a play, just like on defense, there are condensed play calls that are translated into more complicated plays in the heads of each player. An example of a running play the quarterback would call in the huddle would be:
Pro Left 25 Power
The first word denotes the formation of the offense; in this case it is the Pro Set, a one tight end, two wide receiver formation where the fullback and running back line up at equal depths in the backfield, one player to either side.
The second word indicates the strong side of the formation, generally the side featuring the tight end and flanker (a wide receiver lined up away from the line of scrimmage) in most formations. The split end receiver lines up on the opposite (weak) side, on the line of scrimmage. The tailback also lines up on the weakside. There are formations where there are exceptions like I-form, where the tailback is lined up neither left nor right, since the tailback is inline with the fullback and quarterback, or trips bunch, where all three receivers are on the same side.
The first digit in the number ('2' in the above example) denotes who the ball is going to:
10 - Quarterback
20 - Tailback/Running Back
30 - Fullback
40 - Third running back or slotback 333333
The second digit in the number ('5' in the above example) denotes where the ball carrier will pass through the line (between two linemen, called the "hole"). The holes are even to the right of the center and odd to the left of the center. In this case, TE T G C G T
^ ^ ^ ^ ^ ^ ^ ^
7 5 3 1 0 2 4 6
As indicated above, the "1" gap is between the left guard and center, the "0" hole refers to a play going through the center (usually a quarterback sneak) and the "2" hole refers to the gap between center and right guard.
The last word indicates the type of play. In this case ("power"), the fullback would be leading the running back through the hole.
The receivers have their own designations too:
X - Split End
Y - Tight End / Slot Receiver
Z - Wide Out / Flanker
Here is a diagram of how the formation would look based on the play called: Y T G C G T X
Z QB
FB TB
Were this to be the Base I formation, with the tight end on the right, then there would be a 6 hole, which would be outside the tight end. As it is, this play would be a run between the tackle and the tight end.
Passing uses a different type of naming. Since it is not always certain who the ball is going to, each receiver has a route. An example is:
I Y-Motion 245 H-Swing
Again, the I is the formation, and there is no formation modifier word this time. However, there is the "Y-Motion" call (this is an arbitrary name, there are different ways of calling motion for every coach.). In this case it refers to the Y-receiver, and calls for him to motion across the formation to the other side moments before the snap is called. This time the digits correspond to 3 different receivers, and each digit represents a number on the passing tree. The first digit is the X receiver, the second is the Y receiver, and the last is the Z receiver.
0 - Quick hitch
1 - Quick out
2 - Slant
3 - Deep out
4 - Drag
5 - Corner
6 - Curl
7 - Wheel
8 - Post
9 - Fly
In this case, the split end is running a slant, the tight end is running a drag, and the wide out is running a corner. The H-Swing call is a route for the backfield, in this case a swing route for the halfback (tailback). This call is optional, the absence of which calls for the halfback to block.
In both running and passing plays, blocking schemes are tacit and rehearsed. Different types of plays call for different schemes and those differences can also be encoded in the play. For example, plays in the 200s might designate play action pass protection whereas the 300s might refer to a blocking scheme designed for long QB drops. Passing plays call for the linemen to step back and protect against the pass rush, with the backs and tight ends occasionally helping. There is variation to this, in the form of sprintouts, rollouts, play action passes and screen passes. Running plays call for the linemen to get a push against the defense, moving forward to help the running back gain yardage by opening holes and blocking would-be tacklers. Variations may be pulling guards (often used on trap, counter, and other plays to the outside) and