Wikipedia:SIG

Signing your posts on talk pages (normally using four tildes (~~~~)), both for the article and non-article namespaces, is good practice, and facilitates discussion by helping identify the author of a particular comment. Other users can then navigate to a talk page and address their comments to the specific, relevant user(s). Discussion is an important part of collaborative editing, because it helps all users to understand the progress and evolution of a work.

Comments posted on user talk pages, article talk pages and other discussion pages should be properly signed. Signature use that is intentionally and persistently disruptive may lead to blocks.

When editing a page, main namespace articles should not be signed, because the article is a shared work, based on the contributions of many people, and one editor should not be singled out above others.

Furthermore, signatures also serve a technical purpose: various user scripts and talk-page archiving bots, including lowercase sigmabot III, rely on their time stamps to know when to archive old threads. It's because of this that it's also important to avoid overly customizing the date output of a signature, as doing so can lead to stale threads persisting long after they'd otherwise be archived.

There are two ways to sign your posts:

The four tildes will be automatically replaced with your signature after you have saved the changes, as follows:

Since typing four tildes adds the time and date to your resulting signature, this is the preferred option for signing your posts in discussions.

Note that if you choose to contribute without logging in, regardless of whether you have an account, you should still sign your posts. In this case your IP address will take the place of your username, and will link to your contributions history. Your IP address might look something like 192.0.2.213 or 2001:DB8:CEEE:21B:DB60:07FE:4277:63FF.

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