This article is from the Fitness FAQ, by Jeff Gleixner (glex@cray.com) with numerous contributions by others.
MILITARY PRESS
Set-up: Seated with hands at shoulder height, palms forward, arms
in the same plane as the upper body.
Movement: Press up until arms are straight above the head. Lower
back to starting position.
Adding Resistance: Dumbbells or a barbell may be used.
Variations:
Can be done standing.
Behind the neck press: Same movement except the bar travels
behind the head. This should be done by the shoulders
moving the bar back, not the head moving forward or the
chin down.
Arnold Press: Start with palms facing each other, instead of
facing forward, and using dumbbells. Rotate hand forward
while pressing, rotate the hands toward each other while
lowering the weight.
Muscles Worked: Front & Rear Deltoids (Anterior and Posterior
Deltoid), Back of upper arms (Triceps)
LATERAL RAISES
Set-up: Standing with a shoulder wide stance knees slightly bent.
Arms, slightly bent, hanging in front of body, palms facing
each other.
Movement: Lift arms out and away from body, using the shoulders,
until the hands are at shoulder height. In the top position
the arms and body would resemble the letter "T". Lower arms,
using the shoulders, back to the starting position.
Adding Resistance: Usually done with dumbbells or by using a
Lateral Raises machine.
Variations:
At the top of the movement turn the hand in a "Tea pouring"
motion.
Lateral Raise machine: Seated with arms resting on the pads.
Push out and up on the pads, with the forearms/elbows, to
shoulder height.
Palms up Lateral raises: The same as normal raises except the
palms are facing away from each other at the beginning
and face the ceiling at the top and the starting position
has the arms out away from the sides of the body.
Front Raises: The arms are lifted and lowered in front of the
body.
Muscles Worked: Middle of shoulder (Medial Deltoid), Posterior
Deltoid, forearms.
BENT-OVER RAISES
Set-up: Seated, or standing, bent over so the upper body is
parallel with the ground. Shoulder wide stance with the
knees slightly bent. Arms, slightly bent, hanging in front
of body, palms facing each other. Head up.
Movement: Lift arms out and away from body, using the shoulders,
until the hands/elbows are at shoulder height (trying to fly).
Keep the rest of the body motionless. Hands face the floor at
the top of the movement. Lower arms, using the shoulders, back
to the starting position.
Adding Resistance: Usually done with dumbbells or by using
a low pulley.
Variations:
Seated: Sit on the end of a bench, extend legs so there's
enough room for the dumbbells. Bend forward until the
chest is almost on the thighs, hands hanging down under
the knees. Movement is the same.
Muscles Worked: Back of shoulder (Posterior Deltoid)
 
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