OAuth 2.0 and OpenID Connect (OIDC) are two widely used identity protocols that help users securely authenticate with and delegate permissions to third-party apps. When you log in to a service with Google, Twitter, or GitHub, you're most likely using OIDC!
Here are some resources for learning more about OAuth 2.0 and OIDC:
Nate Barbettini's short explainer of OAuth and OpenID. If you have more time, he goes into more detail here
Okta's Illustrated Guide to OAuth and OpenID Connect. If you prefer this content in text, it is also available as an article here.
