Internal Linking
Internal linking is important for both user experience and search engine crawlers, to help them find relevant and important pages. Our SEO Office Hours recaps on internal linking topics cover queries including the importance of internal links for SEO, how anchor text is used as a ranking signal, and how Google handles internally linked parameter URLs for indexing.
For more on internal linking, check out: 5 Internal Linking Strategies to Boost SEO and Drive Organic Traffic
High Volume of Sitewide Links Make It Harder To Understand Connections Between Pages
John recommends against high volumes of sitewide navigation links which make it harder for for Google to understand the connections between the pages.
Many to One Canonical Tags May Be Ignored
Google will try to follow canonicals by default, but they ignore canonical tags if there are significant content differences, or if a lot of URLs canonicalising to the same page, if they think it’s a mistake.
Google Crawls Repeated Links Where One is Nofollowed
If you have 2 links on a page to the same target, but one is nofollowed, then Google will just crawl the followable link.
Title Attribute on Links is Ignored
Google ignores the title attribute in anchor links, but does use alt tags for images inside a link.
Anchor Text is Used for Relevancy
Google does include anchor text for links in to a page for ranking relevancy.
Nofollow Is Ok to Control Googlebot
It’s OK to use nofollow on internal links to control Googlebot behaviour but you need to be careful you are not making it hard for your site to be crawled.
Link Position Doesn’t Affect Their Value
In general Google does not treat links differently depending on their position on the page.
Boilerplate Content Makes it Harder to Find Relevant Content
If your navigation is very large, it can add a lot of text to the page which might make it harder for Google to identify the parts of the page which are relevant. Google is trying to identify boilerplate elements which it can ignore, but the harder this is, the more likely that genuine content might not get classified as relevant.
Content Behind Search Forms May Not Be Seen
Google will have trouble finding all the content on sites with a large number of pages which can only be reached through a search form. John recommends some kind of sensible linking structure.
Anchor Text Counts as Page Content
Google does use the anchor text on internal links to understand the content of pages, but also says that links are treated as text on the page so you should avoid stuffing them with keywords.