How Google works
Query
"Hey Google, I have a question!"
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Google's Web Server
Google web servers send a query to the index servers. The content inside the index servers is similar to the index in the back of a book—it tells which pages contain the words that match the query.
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Index Servers
The query travels to the doc servers, which actually retrieve the stored documents. Snippets are generated to describe each search result.
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Google User
The search results are returned to the user in a fraction of a second.