Learning Level: MULTIPLE

The hole numbering system is based upon the simple formula that even holes are to the right, while odd holes are to the left.  The exception is the zero hole, which is direction over the center.  Furthermore, it should be noted that the middle of the gap may not designate the "exact" location of the hole.  For each play, the hole may shift slightly.  For example, the hole in the  "off-tackle" play is generally considered the outside leg of the playside tackle.

Primary.  Holes 0-8 are the traditional running lanes for running plays.

Advanced. There are an additional four holes, 9-12, which are "imaginary" holes which exist primarily for the purposes of formationing.  These imaginary holes are defined as follows:
    9: left side, between the tackle/end and the furthest receiver
    10: right side, between the tackle/end and the furthest receiver
    11: left side, outside the furthest receiver
    12: right side, outside the furthest receiver