A function that maps an input onto itself is called an identity function. In other words, the output of the function is the same as the input. The identity function is represented by the equation f(x) = x.

The identity function.

i believe it is a linear line

going diagonally

x2 - y2 = (x + y)(x - y) is an identity, not a function.

The purpose of an identity manager system is split into three areas. The pure identity function, which involves the creation, storing, and deleting of identities. User-access function, which allows certain people to access certain devices or services. And the service function, which delivers personalized content to users and their devices.