Curl

In vector calculus, the curl is a vector operator that describes the infinitesimal rotation of a vector field in three-dimensional Euclidean space. At every point in the field, the curl of that point is represented by a vector.
Given a vector field formula_1, the curl of formula_1 can be written as formula_3 or formula_4, where formula_5 is the gradient and formula_6 is the cross product operation.