Topic clusters and recommender systems can help SEO experts create a scalable internal linking architecture. Here's how to build your own.

What is TF-IDF? While using the TF-IDF technique isn’t exclusive to the world of SEO, Moz defines it best: TF-IDF stands for t erm f requency- i nverse d ocument f requency.

Learn what TF-IDF is, how it works, why it’s part of the SEO lexicon, and most importantly – whether Google uses it as a ranking factor.