CODE EXAMPLE FOR SHELL

git ~ vs ^

G   H   I   J
  /      /
  D   E   F
     |  / 
     | /   |
     |/    |
      B     C
          /
         /
         A
A =      = A^0
B = A^   = A^1     = A~1
C = A^2
D = A^^  = A^1^1   = A~2
E = B^2  = A^^2
F = B^3  = A^^3
G = A^^^ = A^1^1^1 = A~3
H = D^2  = B^^2    = A^^^2  = A~2^2
I = F^   = B^3^    = A^^3^
J = F^2  = B^3^2   = A^^3^2

(think of this as git branchs)