Here`s the four primary types of shots, or flights, if you want to call it
that:

Hyzer - This is how the disc flies when it is overstable.  For a righty,
hyzer will be flying and turning left.

Turnover - This is what happens when you release the disc with hyzer(to turn
left for a righty), and it flattens out and then “turns over” so that it
start flying and finishes right.  It turns over to the opposite direction a
disc normally flies.

Anhyzer - This is a shot that you release with an inverse angle from the way
it normally comes out of your hand.  An anhyzer shot, for a righty, will
start off with the angle turned to the right, and will stay angled to the
right and moving to the right throughout the flight.

Helix - This shot is sort of in between an anhyzer and a turnover.  You
release it angled to the left like a turnover or hyzer shot.  During the
flight the disc turns over, much like a turnover shot.  The difference is at
the end of the flight.  A helix shot will straighten out and turn back left
again before the end of the flight.  Basically this results in an “S” turn
throughout the flight.  This is great for accumulating distance because of
all the time it takes for the disc to complete its flight.

A common question we receive at the store and site:

“I never have completely understood the over/under stable thing…Helix?”

Here`s a primer -

Overstable means that, if you throw right handed, the disc will have a
tendency to hook real hard to the left.

Understable will be the opposite, and the disc will have the tendency to
“turn over” to the right.

Stable means the disc should have the tendency to go fairly straight, but
stable will mean different things to different people.  I suspect that, for
most people, a disc that is labeled as stable will tend to hook left to a
degree.  The more stable or overstable the disc, the more it will hook left
for a right-handed player.

All of the above will be the exact opposite for a left-handed player.