Question: what are jr lines in tokyo?
Answer: Yamanote Line. Circle line that connects all major city centers.
Keihin-Tohoku Line. Runs parallel to the Yamanote Line on the eastern half of the circle.
Chuo/Sobu Line (Local) Runs across the Yamanote circle (local slow service).
Chuo Line (Rapid) ... 
Saikyo Line. ... 
Shinkansen.