Before implementing authentication, we need to delve into the theoretical aspect of this matter.

Authentication is like proving you are who you claim to be when using websites or apps. It's a way for a system to check if the person logging in is really the right person.

Real-World Example

When you log into your favorite social media site, you enter your username and password. That's authentication – confirming that you are the account owner.

But sometimes, for added security, they might also send a code to your phone. This extra step is like a double-check (2-factor authentication). Even if someone knows your password, they can't get in without that special code from your phone.

Authentication vs Authorization

In web development, these two concepts play different roles:

• Authentication: It's about proving you are who you say you are. This is done with things like a username and password;
• Authorization: After confirming your identity, authorization decides what parts of the app or website you're allowed to use.

Real-World Example

Think of it like going to a gym. First, you show your membership card (authentication - proving you're a member). Once they confirm that, they decide which areas of the gym you can access (authorization - what you're allowed to use).