As we know that some browser doesn't support frames. If you use frames in your html and what if the browser doesn't support frames?? For that HTML has a special tag <NoFrames> ... </NoFrames>.
Deprecated : FRAME & FRAMESET tags are not supported in HTML5 , better to avoid.
Use <iframe> instead.
<NoFrames> ... </NoFrames>:
<NoFrames> holds the text that should be displayed in the browsers that doesn't support frames.
Note: <NoFrames> .. </NoFrames> tags should be present within <Frameset> ... </Frameset> tags.
Example:
<frameset cols="50%,50%">
<frame src="frm1.html">
<frame src="frm2.html">
<noframes>
<body>This browser does not support frames
</body>
</noframes>
</frameset>