External links is a topic we are regularly asked about and what is best for SEO.
External Links are hyperlinks that point at (target) any domain other than the domain the link exists on (source).
In basic terms, if another website links to you, this is considered an external link to your site. Similarly, if you link out to another website, this is also considered an external link. Pretty simple eh?
<a href="http://www.external-domain-example.com/" title="Keyword Text">Keyword Text - also known as anchor text</a>
The optimal format is to include a target keyword in both the (title) and the (anchor text).
You can also include images into a external link structure. I.e add your logo to a link often referred as a badge.
You will notice that there is no wording. We placed the image where the anchor text would normally go.