In a nutshell, the OpenID technology makes life simpler by having only one username and password to remember.
Once you have enabled your Yahoo account for OpenID access, you only need to remember your Yahoo ID and password to use hundreds of websites... So bid farewell to password spreadsheets and stickies all over your desk!
When you are on a website that supports OpenID login, simply look for a Yahoo login button. Or if you see a text box with an OpenID icon, simply type in "yahoo.com". You will be sent to Yahoo to verify your Yahoo ID and password, and then you will be able to continue on.
For people who prefer pictures, here are the steps:
When using OpenID, you should not enter your Yahoo ID and password on any website other than Yahoo.
If you haven't already done so, we strongly recommend setting up your free Yahoo sign-in seal. A sign-in seal is a personalized image or a message that will only appear on genuine Yahoo pages.
To help prevent the bad guys on the Internet from stealing your Yahoo account data, always look for your sign-in seal before typing your Yahoo ID and password.
Set Up A Sign In Seal
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