The document discusses the evolution of search engine optimization (SEO) techniques over time from 1993 to the present. Early SEOs discovered link manipulation tactics like link farming to boost rankings, but search engines later updated algorithms like Google Panda and Penguin to curb low-quality and spammy links. As search evolved to incorporate social media, location data, semantic meaning, and voice queries, SEO had to adapt as well by focusing more on original, high-quality content and the user experience.