The <script> tag is used for declaring a script (such as JavaScript) within your HTML document.

Example Code:
<script type="text/javascript">
document.write("Hello World!")
Attribute Definition
src Specifies a URI/URL of an external script.
type Specifies the scripting language as a content-type (MIME type).
defer Declares that the script will not generate any content. Therefore, the browser/user agent can continue parsing and rendering the rest of the page.
charset Defines the character encoding that the script uses.
Global Attributes:

The <script> tag also supports the Global Attributes in HTML5