Iframe embed features can be used to embed a webpage inside another page.
There are often reasons why this might be needed, such as embedding processes from an external related website into your own to improve the customer experince and improve conversion or the sharing of content.
Caution should be used when embedding third party content into a site you own. It is important you don’t try and pass off the content as your own for copyright and usability reasons. To over come this a clear title defining the embedded content can be used.
This is an external page (it belongs to the NHS)
<iframe width="100%" height="600px" src="http://www.nhs.uk/Conditions/Meningitis/Pages/Symptoms.aspx"></iframe>