Imagine your study has a billion books, and you want to find the line “Life is like a box of chocolates.” You have no idea which book it’s in or on which page.
If you flipped through them yourself, you’d still be searching in your next life.
That’s when you need a magical librarian: you whisper “Life is like a box of chocolates,” and in a split second he replies: “Forrest Gump, page 143, left column, third line.”
A search engine is exactly that magical librarian for the entire internet.
Right now there are roughly 600–1,000 billion web pages online (no one knows the exact number), and they’re being added, deleted, and changed like crazy every single day. The job of a search engine is to keep the whole internet in its head and, in the 0.3 seconds after you hit Enter, hand you the most trustworthy answers.
How does it actually work? (Explained without any tech jargon)
A search engine is basically a tireless spider (yes, it’s literally called a “web spider”):
- It crawls everywhere It starts at one page, follows every link it finds, rolls like a snowball to the next page, the next, and the next… 24/7, nonstop. It makes a copy of every page it can reach and stores them in its gigantic warehouse.
- It tears every book into words The pages aren’t just piled up as-is. It breaks them down like Lego bricks into individual words (in Chinese this is called “word segmentation”). For example, when it sees the sentence “Beijing’s best roast duck is at Quanjude,” it makes a note: – “Beijing roast duck” → appears on this page – “Quanjude” → also appears here Then it builds a massive phonebook for every word: which pages contain this word?
- It secretly scores every page Not all pages are equally trustworthy. It quietly watches things like: – How many people click this page? – How many important sites link to it? (Like academic citations) – Is the content updated regularly? – Do users bounce away immediately? (That means it’s probably rubbish) It combines hundreds of signals and gives every page a hidden “authority score.”
- The moment you search, it calculates the answer You type “best Peking duck in Beijing” into Google or Baidu. In a flash it: – Finds every page that contains the words “Beijing,” “roast duck,” “best” – Ranks them by the authority score + relevance – Throws the top ten most reliable ones at you All in under half a second.
