basics of smith chart
you draw smith by knowing it is the complex reflection plane.
you have circles of constant resistance, and circles of constant reactance....as well as constant admittance (?)
you go round circle concentric and that is phase change along the line.
it was developed at start of world war 2 by a Gentleman called P. Smith.
Because they developing radar.
and smith chart made the complex calculations easier as you could do them on the graph.