What is Dependency Injection in Angular, and how do the @Self, @skipSelf, and @Optional decorators function within it?

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Dependency Injection in Angular allows for the injection of dependencies into components, services, and other Angular constructs.

Dependency Injection is a design pattern in which a class receives its dependencies from external sources rather than creating them itself.
@Self decorator specifies that the dependency should be resolved from the current component or directive, rather than looking up the hierarchy.
@SkipSelf decorator specifies that the dependency should be resolved from a parent injector, skipping the current component's injector.
@Optional decorator specifies that the dependency is optional, and if not found, Angular will not throw an error.
Example: @Injectable() class DataService { constructor(@Self() private logger: Logger) { } }

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