Lesson 2 / 32

How Search Engines Work

Understanding crawling, indexing, and ranking to optimize for search visibility.

Crawling and indexing

Search engines use bots (crawlers) to visit web pages, follow links, and read content. The content is then stored in a massive index. If a crawler can't reach your page or parse its content, it won't be indexed — and won't appear in search results.

Ranking signals

Ranking depends on hundreds of signals: page speed, mobile-friendliness, content quality, backlinks, user experience, and freshness. Google's Core Web Vitals (LCP, FID, CLS) are critical. The goal: rank your site for queries your content answers.

Developers' role in search visibility

You control the technical signals: load time, mobile rendering, structured data, sitemap, robots.txt, and redirects. A site that's technically perfect but has poor content won't rank; one with great content but broken markup also won't rank. Both matter.