Atbash cipher was originally used to encrypt the hebrew alphabet. Nevertheless,it is used as a type of a simple cryptograph today.
Where as it is the reversal of the CV Cipher:
A = Z
B = Y
C = X
D = W
E = V
F = U
G = T
H = S
I = R
J = Q
K = P
L = O
M = N
N = M
O = L
P = K
Q = J
R = I
S = G
T = G
U = F
V = E
W = D
X = C
Y = B
Z = A