What is abstraction in programming?

Abstraction is a mechanism that allows hiding implementation details and providing a generalized view of a system or its components. It focuses on "what" an object does, rather than "how" it does it.

In C#, abstraction is implemented through:

• Abstract classes: Can contain abstract methods (without implementation) and regular members. An instance of an abstract class cannot be created.

  // Abstract class with an abstract method
  public abstract class Shape
  {
      public abstract double GetArea(); // Abstract method
      public string Name { get; set; }
  
      public void DisplayInfo() // Regular method
      {
          Console.WriteLine($"Shape: {Name}");
      }
  }
  

• Interfaces: Define a contract that a class must implement. They contain only method, property, event, and indexer declarations (before C# 8), or can contain default implementations (from C# 8).

  // Interface
  public interface IDrawable
  {
      void Draw(); // Method without implementation
  }
  

Principles of abstraction:

• Encapsulation: Binding data and methods that operate on that data into a single unit. It promotes hiding internal structure.
• Inheritance: Allows creating new classes based on existing ones, inheriting their properties and methods, while adding or overriding functionality.

Application of abstraction:

• Simplifying complex systems.
• Increasing code flexibility.
• Improving maintainability.
• Creating reusable components.