The language accepted by M, denoted by L(M) is
L(M) = {
and
} for some and 
}
The blank symbol, B is not necessary to be considered as a part of M since it cannot move to the right of right - end marker.
The reason behind using the name "linear bounded automation" is derived from the following fact:
If on every input w with |w| = n, a TM is allowed to use only an amount of tape that is "bounded by some linear function" of n, then the computational power of this TM would be identical to the TM which is restricted to use the amount of tape containing n+2 cells (as given in the definition).