  The hull of a linear code $C$ is the intersection of $C$ with its dual code.
We present and analyze the number of linear $q$-ary codes of the same length
and dimension but with different dimensions for their hulls. We prove that for
given dimension $k$ and length $n\ge 2k$ the number of all $[n,k]_q$ linear
codes with hull dimension $l$ decreases as $l$ increases. We also present
classification results for binary and ternary linear codes with trivial hulls
(LCD and self-orthogonal) for some values of the length $n$ and dimension $k$,
comparing the obtained numbers with the number of all linear codes for the
given $n$ and $k$.
