This document provides an overview of the timelines feature on the Oxford English Dictionary (OED) Online website. It explains that users can explore the development of the English language over time through categories like subject area, regions where English is spoken, or the roots of English words. Selecting a category displays its timeline, where hovering or clicking provides more information. Timelines can also be viewed for search results and allow further refining searches. It concludes by thanking users for taking a tour of OED Online and providing links for more information and subscriptions.