Image from WikipediaI read a article about many hidden functions of Google by eimaj
These are 5 things you didn't know Google could do
1.Removing Unwanted Pages
For example, if you were looking for a review of the book "Eragon", and you typed into Google “Eragon review”, many of the links listed are reviews of the movie, not the book. Because you are not looking for a review of the movie, you can remove all pages relevant to the movie by adding “-movie” to the end of your search terms.
This will now display all the pages relevant to "eragon review", but not relevant to "movie".
+ is used to add terms, - to subtract terms, * to multiply terms, and / to divide terms. Besides these basic operators, you can use ^ to work out something to the power of something (for example, “2^4” would be 2 to the power of 4), and "sqrt" to calculate the square root of a number (for example, “sqrt 4” would be the square root of 4).
By typing “define:” before a word, Google will retrieve and display a list of dictionary definitions for that word.
4.Search A Single Website
If you type "site:" and then a website after a search term, Google will search for your term(s) in only the site dictated. For example, the following search will search Oxford University's Website for the term "prospectus."
5.Search for A Specific File Type
For example, if you were looking for a PDF version of the iPhone manual, you could use the following search, which would produce more accurate (and less) results.
Here the "filetype:" tool is making Google search the web for PDF files only, therefore eliminating any pages that we didn't want to see.
So,if you wanna looking for a PDF version of the iPhone manual,you type into Google "iPhone manual filetype:"