How Search Engines Work

 How Search Engines Work

Search engines like Google, Bing, and Yahoo follow a three-step process to show you the most relevant results:

✅ 1. Crawling

Search engines use bots (also called spiders or crawlers) to explore the internet.

• They visit web pages, read their content, and follow links.

• This helps them discover new or updated content.

• Crawlers obey rules from robots.txt files on each site.

📌 Example:
Googlebot finds your site by following a backlink from another website.

✅ 2. Indexing

Once a page is crawled, it's analyzed and stored in a massive database (called the index).

• The index includes keywords, images, site speed, mobile usability, and more.

• If a page can't be indexed (due to errors or blocked access), it won’t show in search results.

📌 Example:
A blog post about “best smartphones” is indexed and added to Google’s database with that topic in mind.

✅ 3. Ranking (Serving Results)

When a user types a query, the search engine:

• Scans its index

• Finds the most relevant pages

• Ranks them based on hundreds of factors (called ranking signals)

🔑 Key Ranking Factors:

• Relevance to the search query

• Quality and depth of content

• Page speed & mobile-friendliness

• Backlinks from trusted sources

• User engagement (bounce rate, CTR)

📌 Example:
When someone searches “buy running shoes,” Google ranks online stores, reviews, and product pages with strong SEO and user trust.

Bonus: Algorithms & Updates

Search engines use complex algorithms to rank results.
Google updates these frequently (like the Helpful Content Update, Core Web Vitals, etc.).