Why is there no registration or login link on the website?

How am I identified on this website. How does my codechef username automatically appear in the posts I make ?

Since a user on CodeChef Discuss is assumed to be a user on CodeChef, there are no separate registration/login links needed here. To use CodeChef Discuss, all you need is a CodeChef user handle. If you already have one, simply log on to CodeChef.com and then if you visit this site, you will be automatically identified. If you do not have a user handle, you should register yourself first on CodeChef.

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