The Online Writing Lab (OWL) at Purdue University houses writing resources and instructional material as a free service of the Writing Lab at Purdue. Students, members of the community, and users worldwide will find information to assist with many writing projects. Teachers and trainers may use this material for in-class and out-of-class instruction. In addition, we invite users to submit brief, writing-related questions to our OWL Mail Tutors. You may also find our new grammar blog useful.
(adapted from website)