Fastball/Change-up
There are several types of fastballs that all act slightly
different. The basic fastball is thrown with a downward snap
of the wrist
As a good fastball gets near the plate, it will
"hop" upward, making it harder to hit by a batter.
A "cut" fastball will move inward on a left-handed batter
when thrown by a right-handed pitcher, while a "tailing" fastball
moves outward.
A change-up or "slow ball" is thrown similarly,
except for that the top two
fingers are lifted just as the ball is released.
The change-up is especially effective against batters if you have a very fast
fastball. The change-up can also be held deep in the palm.
Curveball/Breaking ball
The curveball has a sideward spin that will cause it to break
inward. It is thrown with an outward snap of the wrist that causes
the back of the hand to face the batter. Most pitchers
will apply pressure with the middle finger while using their
index finger to guide the ball as it is released.
Slider
The slider is in essense a fast curveball.
It looks like a fastball until it starts to break.
It is often thrown sidearm and and is pitched faster than a curveball.
The break on a slider is less than a curveball and is down and lateral.
Screwball
The screwball is the exact opposite of the curveball. Instead of breaking
inward, the screwball spins in the towards the other direction and breaks outward.
In order to throw a screwball, the palm has to be turned outward, as
opposed to inward for a curveball.