Google’s original business was creating algorithms to help people sort quickly through the rapidly growing amount of content being put online. Rather than employ editors and researchers to curate links for specific queries, Google began building algorithms that scored the content it was indexing against specific criteria.

These included novel concepts like inbound links from trusted sources as well as standard measures like keyword frequency and page titles. All of these pieces came together in a Page Rank that decided where a site would display on a specific query.

Using this scoring approach, Google was able to serve up more accurate results than many of the existing search engines that preceded it in the market. The algorithm was—and still is—being constantly tweaked and updated to give users the most relevant results. Because it started strong and just kept getting better and better, Google became the go-to search engine for the Internet in the space of a few years.