What is the best way to describe how an Internet search engine works? (Hint: this is why you have to spell correctly when you use a search engine.)

1. A search engine looks up all the library books ever written about the word you typed.

2. A search engine relies on a person who is hired to send you information about the word you typed.

3. A search engine figures out the question you have based on the word that you type.

4. A search engine looks through all the text on the Internet for an direct match to the word you typed.