The <noscript> tag is available in both HTML5 and HTML4.01. It tells, that the browser does not support script. The content present in <noscript> tag will be display when script not support by browser. In HTML4.01, the <noscript> tag can be used in body tag. But in HTML5, It can be use in both <head> and <body>.Declaration Syntax :
<h1>Example of noscript tag!</h1>
Script not supported by browser.
The noscript tag is available in both HTML5 and HTML4.01. So no difference.