Define authentication and authorization
Authentication
Authentication is the process of proving that a person is who they say they are. When someone purchases an item with a credit card, they may be required to show an additional form of identification. This proves that they are the person whose name appears on the card. In this example, the user may show a driver’s license that serves as a form of authentication and proves their ID.
When you want to access a computer or device, you'll encounter a similar type of authentication. You may get asked to enter a username and password. The username states who you are, but by itself isn't enough to grant you access. When combined with the password, which only that user should know, it allows access to your systems. The username and password, together, are a form of authentication. Authentication is sometimes shortened to AuthN.
Authorization
Once you authenticate a user, you'll need to decide where they can go, and what they're allowed to see and touch. This process is called authorization.
Suppose you want to spend the night in a hotel. The first thing you'll do is go to reception to start the "authentication process". After the receptionist has verified who you are, you're given a keycard and can go to your room. Think of the keycard as the authorization process. The keycard will only let you open the doors and elevators you're permitted to access, such as for your hotel room.
In cybersecurity terms, authorization determines the level of access or the permissions an authenticated person has to your data and resources. Authorization is sometimes shortened to AuthZ.