What is Fibration of simplicial sets?

In mathematics, especially in homotopy theory, a left fibration of simplicial sets is a map that has the right lifting property with respect to the horn inclusions Λ i n ⊂ Δ n , 0 ≤ i < n {\displaystyle \Lambda _{i}^{n}\subset \Delta ^{n},0\leq i

On the other hand, a left fibration is a coCartesian fibration and a right fibration a Cartesian fibration. In particular, category fibered in groupoids over another category is a special case of a right fibration of simplicial sets in the ∞-category setup.