Jib
A jib is a triangle sail that is forward of the mast.
They have a number of names, some of them refer to their percentage of overlap, of the mast.
If the aft edge of the jib reaches back to the mast, then it is a 100% jib, also known as a working jib.
If the 10% of the jib extends aft of the mast, then it is called a 110%.
If it has 135-150% aft of the mast, it is commonly called a Genoa.
The very small ones that do not extend aft to the mast are called storm jibs.
The jib typically has 2 sheets attached to it's clew, the tack is attached to the bow or a sprit, and the head is hoisted with a halyard.
Jibs work better with very high luff tension, this helps form the right sail shape.
Sheeting Angle
With a sail that is attached to a mast and has a boom on it, you don't really have to worry about where you mount the sheet (rope that holds the part of the sail that swings around) because the boom keeps it stretched and in good shape.
Head sails (jibs, genoas etc) typically don't have a boom, so where you mount the sheet to the boat is rather important for upwind performance.
If you mount it too close to the centerline, like for instance if you mounted it right next to the mast, as you tried to sail upwind the head sail would look rather like a U shape and not work very well.
On the other extreme, if you mounted the sheet way out to the side, you would not be able to pull the head sail in tight enough and you would not be able to sail close to the wind.
So what is the proper angle to mount the sheet for the head sail? (degrees off the centerline of the boat)? Well, it depends on a lot of factors like your sail's shape, the type of other sails you have, how effecient your keel is etc.
It will require experimentation to determine what is best for your situation, but some good guidelines are that 6 meter and 12 meter boats, who perform very well to windward, use a sheeting angle of 6 degrees off the centerline. Many production fiberglass boats use a sheeting angle more like 10 or 15 degrees.
Staysail
A staysail is a jib which is flown between other sails, such as between the main and the jib.
Spinnaker
These are very pretty sails and can greatly increase your speed going down wind.
There are several versions, the one pictured is a symetrical spinnaker.
They are typically flown free off the bow of the boat, one sheet on the clew, and one on the tack.
The halyard has a swivel on it so when hoisted, if the spinnaker is twisted it can unroll itself.
There are a number of variations of a spinnaker, the most popular being an asymmetrical.
It is more like a very large genoa, having 2 sheets on the clew so it can be tacked like a jib.
The asymetrical is able to go at greater angles than the symetrical, which is mostly good for straight down wind.
Some of the other names for the spinnakers are: spanker, cruising spinnaker, chute, reacher, drifter, blast reacher, flasher
Mary Poppins Spinnaker
Simplest of all sails, the umbrella.
Many kayakers use umbrellas for sailing down and cross wind.
The trick to using them is to tie strings from the tips of the umbrella back to the handle, this will prevent the umbrella from blowing inside out.
Jib
Spinnaker
Mary Poppins Spinnaker