Address Bar

What is an Address Bar in a Window?

An address bar is a horizontal bar with a text box that displays the current location's address typically found at the top of a window of an application that can navigate from one place to another, such as web browsers and file managers. In such applications, each location that the application can show is identified by a text code called its "address." What this address code looks like depends on what the application displays. In file managers, it's the filepath of the folder whose contents are displayed, e.g. C:\folder\. In web browsers, it's a URL that uniquely identifies a resource on the Internet, e.g. https://www.example.com/.

Notable Features

Hidden address code: in some address bars, the actual address code is hidden until you click on the bar. The address code is text code, and it's possible that by default this text code is turned into buttons for easy navigation or it hides commonly repeated parts of the code. For example, in some web browsers, accessing https://www.example.com will display example.com in the address bar until you click on it. Note that, technically, https://www.example.com and https://example.com are different URLs.

Location history: as you can can navigate from one place to another, applications with address bars tend to keep track of which locations you have visited, and provide a back button to go to the previous location, and a forward button to undo going back.

Hierarchy: often, address code codifies a hierarchy, such as the folder hierarchy in a file system. In this case, there may be a button to go "up" in the hierarchy. For example, if the address bar shows:

C:\folder\subfolder\

Then clicking "up" goes to:

C:\folder\

Which is the parent folder.

In URLs, the same doesn't work. A URL uniquely identifies a resource on the Internet. You can have a valid URL code that don't point to a resource that actually exists. For example, if you have the URL:

https://www.example.com/category/article

Then going "up" the hierarchy should get you:

https://www.example.com/category/

Although this make sense looking at the URL code, that doesn't mean the website actually has a webpage for each of its categories, or even that they would be URLs like these specifically. For example, it could be that website has articles in URLs ending in /entertainment/article, and it has a webpage for the entire entertainment category, but this webpage isn't at the address /entertainment/, instead it's at the address /categories/entertainment. When it comes to URLs, it's not possible to make the same assumptions we would be able to make with filepaths.