HowYouBuildIt - ASL American sign language for the deaf.
How to sign the ASL alphabet

Background
ASL is American Sign Language. The ASL alphabet is a finger spelling method of representing the letters of the alphabet. ASL is used by the deaf community to communicate. It is used to spell words as needed. Also many signs are based on the hand positions of the alphabet.

ASL alphabet
A
A
 B
B
 C
C
 D
D
 E
E
 F
F
G
G
 H
H
 I
I
 J
J
 K
K
 L
L
M
M
 N
N
 O
O
 P
P
 Q
Q
 R
R
S
S
 T
T
 U
U
 V
V
 W
W
 X
X
Y
Y
 Z
Z
J is different from the other letters in that it is a motion not a single postion of the fingers. It starts with the I position and traces a curve by turning the wrist without changing the position of the fingers. The motion ends with the back of the hand visible.
Z, like J, is a motion not just a position of the fingers of the hand. Z uses the D finger position but traces out an imaginary Z motion in the air.