Order of a general linear group over a finite field
= Order of a general linear group over a finite field
Choosing linearly independent columns successively gives
$$
|GL_n(\mathbb F_q)|
=(q^n-1)(q^n-q)\cdots(q^n-q^{n-1})
=q^{n(n-1)/2}\prod_{k=1}^n(q^k-1).
$$