It's a common misconception that Google "knows everything." While Google is a powerful search engine and has an enormous amount of information, it does not have omniscience or access to all knowledge.
Google's vast database is built through a process called web crawling or indexing. Google uses automated programs called "spiders" or "bots" to crawl the web and index web pages. These bots follow links from one page to another, effectively mapping the structure of the internet. When you type a search query into Google, it retrieves relevant information from its index and presents it in the search results.
However, the information that Google has access to is limited to what is publicly available on the internet. It doesn't have access to private or proprietary databases, personal information stored behind logins or firewalls, or classified information. Additionally, Google's index is continually being updated and doesn't necessarily capture real-time information, although it does its best to provide the most up-to-date results.
Google's impressive ability to find relevant information quickly comes from its sophisticated algorithms and extensive infrastructure. It uses machine learning and artificial intelligence techniques to understand user queries better and return more accurate results.
While Google is undoubtedly a valuable tool for accessing a vast amount of information, it's important to recognize that it's not all-encompassing and there are limitations to what it can provide. There are still many areas of knowledge and information that are not readily available on the internet or indexed by search engines like Google.