When you use someone else's work in your own academic work, you must give them the CREDIT.
Failure to do so is plagiarism, or the stealing or passing on of another's work as your own.
Examples of intentional plagiarism are:
copying a friend's work
cutting and pasting blocks of text
borrowing images without citing the original source
Examples of unintentional plagiarism are:
failure to use your own ideas
An easy source to create a bibiliograghy or works cited page can be found at one of these websites:
For an interesting tutorial about plagiarism, visit this website set up by the University of Texas librarians: