Access controls are security measures that determine who can view or use resources in a computing environment. They help protect sensitive information by restricting access to authorized users only. This can include physical access to buildings or digital access to files and systems. There are various types of access controls, such as role-based access control (RBAC), which assigns permissions based on a user's role within an organization. Other methods include mandatory access control (MAC) and discretionary access control (DAC), each with different levels of user authority and flexibility in managing access rights.