What are the differences between AngularJS and Angular with respect to dependency injection?
Dependency injection is a common component in both AngularJS and Angular, but there are some key differences between the two frameworks in how it actually works.
| AngularJS | Angular |
|---|---|
| Dependency injection tokens are always strings | Tokens can have different types. They are often classes and sometimes can be strings. |
| There is exactly one injector even though it is a multi-module applications | There is a tree hierarchy of injectors, with a root injector and an additional injector for each component. |