Can you give examples of methods that do not change the system state upon repeated calls?

Methods that do not change the state of the system upon repeated calls are called idempotent. Examples of such methods:

• HTTP GET requests, which simply return data without modifying it.
• Methods that return a computed value without changing the internal data of the object.
• Functions that always return the same result for the same inputs (pure functions).

For example, a method that retrieves user information by ID, which does not change data in the database but only reads it.