The wordpress admin bar is always at the top left of your website and it is the name of your website. It is only visible if you are logged into your wordpress dashboard. See the picture below I have taken whilst writing this post in the back end, at the top left is the name of my website and that is the link to the admin bar while viewing your site.
Now you can see that this same admin bar is available to you for quick access to your editing tools whilst you are viewing your actual website whilst logged into your dashboard.
The idea behind it is to allow you easy access to your dashboard directly from your site without the added bother of having to jump back and forth between the front end (your website) and the back end (your wordpress dashboard). Think of is as a way to provide some handy shortcuts to your wordpress installation. Visitors to your website will not be able to see any of this so don’t worry about that because they aren’t logged in to your wordpress dashboard. If you don’t want to have it visible for yourself you can turn it off by selecting your user name at the top right hand side of your dashboard, then select edit profile, then turn the toggle off next to the “show toolbar when viewing site”. Remember, whenever you make changes that you have to always select “update” at the bottom of the page for the changes to be saved.