To have a legit answer in your assignments/projects. Not everything you see and browse the internet is a fact, some of them are just bluff or prank. It's better to use, sometimes the library. 
the library is where you can find a reference on the word and library is find in school; if you dont finished or not sure about it just go to the library and search about the reference
It is more advisable to search your assignment in library it is because it is more accurate than to search it in the internet.