They are the end points of the graph!
a graph key is when one end of the graph goes into a nother graph and makes baby graphs.
If the graph start and end with same vertex and no other vertex can be repeated then it is called trivial graph.
point
a scatter graph
HMS Graph was created on 1941-05-15.
HMS Reclaim ended in 1979.
HMS Macedonian ended in 1828.
HMS Folke ended in 1919.
HMS Largs ended in 1968.
HMS Malaya ended in 1944.
HMS Ejdern ended in 2004.
HMS Beagle ended in 1845.
HMS Endeavour ended in 1774-09.
HMS Abatos ended in 1946-03.
HMS Göta Lejon ended in 1984.
HMS Emperor of India ended in 1931.