Can you explain what access control is and why it is needed in systems?

Access control is a mechanism that determines who can perform what actions within a system. Its main purpose is to protect resources and data from unauthorized use.

In systems, access control helps to:

• Limit access to confidential information.
• Prevent accidental or malicious data modifications.
• Ensure the security and integrity of the system.

Example: In an iOS application, access control can be implemented through permissions — for example, access to the camera, microphone, or geolocation. The user must explicitly grant the application permission to use these resources.

Additionally, in programming code, access control is implemented through access modifiers (public, private, internal), which restrict the visibility and usage of classes, methods, and properties, helping to structure the code and prevent improper use of components.