This FAQ was last updated: Dec 12, 2014 Views: 490
If you are faculty member there are ways you can check for plagiarism. Check with your department head to find out how to access tools for identifying plagiarism.
If you are a student, "Florida State University defines plagiarism as "Intentionally presenting the work of another as one's own (i.e., without proper acknowledgement of the source). "
If you use the above definition while completing your work you will not need a tool to identify plagiarism in your own work. Also see the Research Guide that helps you to identify what is and ian't plagiarism. Go to http://guides.lib.fsu.edu/plagiarism
However, there are free tools online, such as http://plagiarisma.net/, but I haven;t checked it completely and suggest you take a look.