How Search works?

Hi friends,
today i have discussed a topic with my friends which is how search works?
I got this question few months back and got the answer from these
websites
which i usually use to find answers to my questions

1. Infotoday 
2. howstuffworks &
3. youtube 

my description for this question is we know/learned some algorithms for searching

patterns such as binary search for ordered list of items but those we have learned 

are limited to less sized data but searching entire internet we need much better which 

is spider search (google uses it). For more explanation refer above links and if u saw the

linked video u will understand much effectively.