WordPress admin bar is a menu bar you will see at top of the screen with useful dashboard links. You can see alerts, add posts, manage recent comments and other related tasks.
The Admin bar was first introduced in WordPress 3.1
Admin bar is a great way to directly access dashboard functions which you use on daily basis. Additional features can be added using plugins.
Admin bar on the front page
You may have noticed that the same admin bar is visible on your website’s front page also. The front admin bar is an easy way to perform common tasks without going into dashboard at the backend however users can switch if off depending upon their personal preference.