We learned how links can affect the ranking of your site.
Now let's see what links are in terms of the text enclosed within them (anchor).
Just in case, I remind you that hyperlinks in Html are a structure of the form:
"path to the web page file "
anchor (the text that will be the link)</a>
Therefore, the following backlink options are possible (backlinks to your website):
Unanchored - despite the name, the text is present in such links, but it is extremely difficult to rank on it by search engines, because this text is some common words like the adverbs “here”, “here”, “there” or other common words (for example, "this site").
They can also include backs, where the address of this website acts as text (its URL, for example, is https://google.com).
What are they needed for?
Obviously, to dilute the anchor list (these are the texts of all links leading to this page you are promoting).
This gives the reference mass a touch of naturalness. What is noteworthy, search engines, even from non-anchor backlinks, are trying to squeeze out some information that could be useful in ranking.
Therefore, they, having not found anything meaningful in the text of the link, begin to search somewhere nearby, and can take into account as a anchor the near-link text (before or after the link). You can help them and put together keywords or their synonyms.
With the direct entry of keywords, this is the most common and obvious type of anchor, for it is enough to simply take the search query by which you plan to promote this page of your site and surround it with opening and closing hyperlink tags.
No need to invent anything.
This is precisely their weak point, because the purchased essence of such backlinks is visible to search engines even with the naked eye. Judge for yourself.