The WordPress Upgrade Notification Process
After you install WordPress and log in for the first time, you can see the version number on the WordPress Dashboard.
Therefore, if anyone asks what version you’re using, you know exactly where to look to find out.
An upgrade notification bubble appears on the left side of the page.
Say you have WordPress installed and you’ve been happily publishing content to your website with it for several weeks, maybe even months, and then one day you log in to your Dashboard and see a message at the top of your screen you’ve never seen before that reads, WordPress X.X.X is available! Please update now.
Both the message at the top of the page and the notification bubble on the Dashboard menu are visual indicators that you’re using an outdated version of WordPress and that you can (and need to) upgrade the software.
The message at the top of your Dashboard includes two links that you can click for more information. The first is a link called WordPress 3.x. Clicking this link takes you to the WordPress Codex page titled Version 3.x, which is filled with information about the version upgrade, including installation/upgrade information, summary of the development cycle for this version, and the list of files that have been revised.
The second link, Please Update Now, takes you to another page in the WordPress Dashboard — the WordPress Updates page.
At the very top of the WordPress Updates page is another important message for you:
Important: before updating, please backup your database and files. For help with updates, visit the Updating WordPress Codex page.
Both links in the message take you to pages in the WordPress Codex that contain helpful information on creating backups and updating WordPress.