Its been more than 10 years since nofollow attribute became a part of HTML and web. It is the recommended way by which Google identifies which links are legitimate and trusted by the author and which are user generated spam.
Today Google is improving this further by introducing two more values for the rel HTML attribute which will make it easier for webmasters and web crawlers to distinguish between spam and user generated content. These two new attribute values are explained below:
<a rel="sponsored">Tech Curiosity</a>
This “sponsored” is the new value for rel attribute. Use this attribute to mark links on your site that were created for advertisement or sponsorship purpose.
<a rel="ugc">Tech Curiosity</a>
UGC is the second new value for rel attribute which stands for User Generated Content. This value is recommended for those links which are generated by the users in comments, forums posts, etc.
If you provide guest posting or public posting on your forum which can link to external web pages, make sure you mark your url using this attribute value.
<a rel="nofollow">Tech Curiosity</a>
Use this attribute value to not recommended or pass link juice to the page. The functionality here will remain same.
Can I use two attributes together?
Yes! you may use more than one value on a link.
For example: rel=”ugc sponsored” tells that the link is sponsored and is created by the user.