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Earthdata Login replies by asking the user agent to provide credentials - a username and password. It may also ask you to confirm that the application be allowed to access some of your user profile information.

Step 5

The user agent send the user credentials to Earthdata Login.

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You can see that your username and password is only sent to Earthdata Login, and not to the application, and Earthdata Login only accepts requests using HTTPS. This helps keep your credentials secure . from prying eyes, and is one less copy of your credentials that you have to worry about being stolen.

Further Reading

For the brave: http://oauth.net/2/

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