Most sailboats are able to sail at a 45 degree angle to the wind - Close Hauled. The sail acts like an airplane wing. The wind on the outside of the sail has to travel farther than the air passing over the inside of the sail. This creates a difference in pressure. On an airplane this creates lift, on a sail boat this creates forward pressure or pushing effect.

Sailing closed hauled is like walking a thin line. If you turn too far windward the sails will luff and you will lose boat speed. Alternatively, if you turn too far downwind your angle to the wind decreases and your overall forward advance is reduced.

Sailing to close to the wind will cause the sails to luff (flutter). If turned directly into the wind the boat will eventually lose all forward momentum and you will not be able to steer - In Irons.

As a general rule, you let out more sail the further you head downwind. When sailing a Close Reach you will ease the sail from the close hauled position.

When sailing a beam reach (directly sideways to the wind) you will let out more sail. Sailing a beam reach is a fast, exciting and comfortable sail. This is when you will find the most boat heel (lean). If the sails are in too tight the boat will heel excessively causing the boat to turn into the wind (weather helm). Weather helm is a sign that you need to let ease your sails for maximum performance.

Broad Reaching requires the sails to be eased further. The boat since now travelling with and across the waves will have a more rolling effect. The sail dynamics have also changed, the boat is now being pushed by the wind as opposed to differences is sail pressure.

Running or sailing directly downwind is an exciting but the most dangerous point of sail. If there is a sudden wind shift the boat could be thrown into an inadvertant gybe causing the boom to swing recklessly across the deck damaging anything standing in it's way.

For the experienced sailor, there is nothing like sailing wing-to-wing (foresail out one side and the mainsail out the other).

Learn and practice your points of sail. Proper use of your points of sail will allow you to sail from one location to another in the quickest and most efficient manner.