The shape of the s subshells is spherical. The shape of the p subshells is the shape of three barbells at ninety degrees to each other. The shape of the d and f subshells is very complex.
Electron configuration is the "shape" of the electrons around an atom, that is, which energy level (shell) and what kind of orbital it is in. The shells were historically named for the chemists who found and calculated the existence of the first (inner) shells. Their names began with "K" for the first shell, then "L," then "M," so subsequent energy levels were continued up the alphabet. The numbers one through seven have since been substituted for the letters. Notice that I have included an "R" shell (#8) that is purely fantasy but makes the chart symmetrical.
The electron configuration is written out with the first (large) number as the shell number. The letter is the orbital type (either s, p, d, or f). The smaller superscript number is the number of electrons in that orbital.