PageRank is a Google algorithm that judges how important a website or an individual page is. The number and the quality of incoming links are what count most.
The underlying idea: if many trustworthy websites link to a page, that page is treated as more important and more relevant.
How does PageRank work?
PageRank rests on the principle that not every link is worth the same. A link from a strong, well-known website can carry far more weight than many links from small or weak ones.
Among the things Google weighs up:
- the number of incoming links
- the quality of the linking pages
- topical relevance
- internal linking
- the strength of individual pages
Part of that link authority is passed on through links to other pages, which is why internal linking within a site matters too.
Why PageRank matters
PageRank was one of the main reasons Google delivered better results than other search engines in its early years.
Today the original PageRank is only one part of a much larger algorithm. The basic idea still holds: good links from strong websites can improve visibility and rankings considerably.
For SEO that means good content alone is often not enough. Authority and links play a large role as well.