What internal links do
A visitor may need more than the page they landed on. A service description can lead to a relevant case study; a tutorial can point to a detailed explanation of one step. A useful link makes that next action easier to find.
Internal links also help search engines discover pages and understand relationships between content. Google recommends using an <a> element with an href attribute for crawlable links.
Choosing a destination
Ask what the reader is likely to need at this point. Choose a page that addresses that need and use clear anchor text. A migration guide, for example, can link to a preparation checklist when it reaches the planning stage.
A link map is useful for inspecting structure. It does not, by itself, tell you why someone would follow a link. Counting links cannot answer that question either.
Putting it into practice
How to connect pages around what visitors need next.
Source
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