SOLID is a set of principles that aim to guide developers in writing maintainable and scalable software. It stands for Single Responsibility Principle, Open-Closed Principle, Liskov Substitution Principle, Interface Segregation Principle, and Dependency Inversion Principle.

Single Responsibility Principle (SRP)

The SRP states that a class should have only one reason to change. In the context of Angular, this principle suggests that a component or service should have a single responsibility or purpose. This promotes code organization and ensures that each class is focused on doing one thing well.

Open-Closed Principle (OCP)

The OCP states that software entities should be open for extension but closed for modification. In Angular, this principle encourages the use of inheritance or interfaces to enable the extension of functionality without modifying the existing code. This promotes code reusability and maintainability.

Liskov Substitution Principle (LSP)

The LSP states that subtypes must be substitutable for their base types. In Angular, this principle emphasizes that components and services should be able to be substituted without affecting the behavior of the application. This promotes modularity and enables easier testing and maintenance.

Interface Segregation Principle (ISP)

The ISP states that clients should not be forced to depend on interfaces they do not use. In Angular, this principle suggests defining specific interfaces for different types of behavior, allowing components and services to depend only on the interfaces they actually need. This promotes loose coupling and better separation of concerns.

Dependency Inversion Principle (DIP)

The DIP states that high-level modules should not depend on low-level modules; both should depend on abstractions. In Angular, this principle encourages the use of dependency injection to decouple classes and promote the use of interfaces as dependencies. This promotes flexibility, testability, and modularity.