The **`base`** element in `HTML` is used to specify the `URI` upon which all the relative `URIs` in the document are built upon. There can only be one `base` element in a document.

`base` must be declared in the `<head>` tag of the document. If a target is also specified in the `base` element, that target defaults to the target of the subsequent hyperlinks. 

# Attributes
* `href`: The URI from which all the subsequent URIs will be resolved. 
* `target`: The default target for all URIs and forms on the page. The `target` specifies how the hyperlinks on the page will open. 


# Global attributes and events

The `base` element includes [global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes).

# Code


<head>
  <base href="https://www.educative.io/" target="_blank">
</head>

<body>
<a href="edpresso/how-to-center-an-absolutely-positioned-element-inside-its-parent">How to center an absolutely positioned element inside it's parent</a>
</body>

codemirror

In the above code, we have set the `base` URL as `https://www.educative.io/` and the target as `_blank`; this will open the hyperlinks in a new tab. The last `<a/>` tag contains the URL for the article *"How to position an absolutely centered element inside its parent"*, but since we are using the `base` tag, we do not have to include the `https://www.educative.io` part in its URL. 

What is the base element in HTML?

Specifies the URI base for relative URIs and default hyperlink targets in an HTML document.

Target	Description
_blank	opens links in a new window
_parent	links will open in the immediate parent context
_self	links will open in the same context that's containing the link
_top	inks will open in the topmost context (the greatest parent context containing the link)