For sign up in any website like Facebook, Pinterest we need to give our email ID. I have been using my Gmail ID almost in every case but after three, four years I have forgotten some sites in which I had created accounts.
There are several different paths you can take to get to the list of authorized sites. Here's one:
- Go to your Google Account Settings
- Click on Security (in the left menu)
- Scroll to the bottom under "Connected applications and sites" click the Manage access button
- You will probably need to re-enter your password as a security measure
- You are presented with a list of all the sites where you've used your Google Account (a.k.a. Gmail address). (You can revoke access for any of these by clicking the button next to it)