link Frontend Masters: Modern Search Engine Optimization (SEO) by Mike North (4 hours 4 minutes) (Jun 15, 2017)
Traditional SEO
Focus on content quality and crawler hints.
Frequent updates, link building.
Keyword stuffing and using long tail keywords (multi-word phrases) to find very specific information, as site visitors are likely to use these keywords when they are closer to a point-of-purchase.
PageRank algorithm assumed “quality” of a site is proportional to the number of links to it. And the value of a link on a “quality site” is worth more.