i am doing my exercises about distribution and this is the density function. tho i have never seen in my lecture the $\mathbf{1}_{[a, b]}(t)$ symbol and i have no one to ask about it. i dont understand what it means and so i cant start any kind of calculation.
$f_{X}(t)=\frac{1}{b-a} \mathbf{1}_{[a, b]}(t)$
can anyone help me with the meaning of it?