Linked from
The 6 pages that link to Ray (geometry), each with the reason it gives.
AngleBroader topic: The two rays forming an angle share their endpoint.
Line segmentCompared with: A ray shares one endpoint with a segment but continues without bound.
Line (geometry)Broader topic: It keeps one direction of a line while adding an endpoint.
Angle bisectorRelated: An angle bisector is a ray whose endpoint is the angle's vertex.
Right angleRelated: Two rays with a shared endpoint can form a right angle.
Directed angleBroader topic: A directed angle starts with one ray and ends with another.