Use of symbols '@', '&', '=' and '>' in custom directive's scope binding: AngularJS

Question

I have read a lot about the use of these symbols in the implementation of custom directives in AngularJS but the concept is still not clear to me.

What does it mean if I

Answer 1

When we create a customer directive, the scope of the directive could be in Isolated scope, It means the directive does not share a scope with the controller; both directive and controller have their own scope. However, data can be passed to the directive scope in three possible ways.

1. Data can be passed as a string using the @ string literal, pass string value, one way binding.
2. Data can be passed as an object using the = string literal, pass object, 2 ways binding.
3. Data can be passed as a function the & string literal, calls external function, can pass data from directive to controller.