OAuth

When you 'connect' one tool to another and it sends you to a familiar sign-in screen to approve, that is OAuth. Instead of giving the app your password, the service issues it a scoped token: access to only what you approved, and only until you revoke it.

It is how automations reach your accounts safely. The token can be limited to specific permissions and pulled back at any time, so connecting a tool never means surrendering the keys to the whole account.