About: Sheaf of logarithmic differential forms

In algebraic geometry, the sheaf of logarithmic differential p-forms on a smooth projective variety X along a smooth divisor is defined and fits into the exact sequence of locally free sheaves: where are the inclusions of irreducible divisors (and the pushforwards along them are extension by zero), and is called the when p is 1. For example, if x is a closed point on and not on , then form a basis of at x, where are local coordinates around x such that are local parameters for .