Katame Waza refers to grappling techniques and is comprised of:
[i] Osae-Komi Waza (hold-down techniques),
[ii] Shime Waza (strangling techniques) and
[iii] Kansetsu Waza (joint techniques).
As can be seen from the terminology, grappling of an opponent can be done, by locking his joints, or by applying hold down techniques (Osae Komi Waza) or by stangling techniques. . Sometimes, the term Ne Waza (mat work) is used parallel to Katame Waza.
This particular technique is usually practiced in kata and never in randori as making forceful contact with a vital point can consequently result in pain, loss of consciousness, coma, disablement or death.
Using Atemi Waza one disable his assailant by attacking. This attack can be in the form of striking, punching, chopping, thrusting or kicking using the fist, the knife edge of the hand, the fingertips, the elbow, the knee, the ball of the foot, the toes, the heel, the forehead or the back of the head.
Atemi Waza are further divided into Ude Waza (arm strikes), and Ashi Ate (leg strikes). In Ude Waza, assilant's vital points are attacked with the hand or arm whereas in Ashi Ate, the leg or foot is used for attack.
The International Judo Federation has officially listed 66 different nage waza techniques, and 29 different Katame Waza techniques (9 Osae Komi waza, 11 Shime waza, and 9 different Kansetsu waza).