Wind
As mentioned earlier, to sail into the wind one must keep the sails quite close to the direction of the boat, as the direction of the boat aproaches the perpendicular to the wind the sails should be slightly further out till they are about 20 degrees from the centerline of the boat. Then as you start moving with the wind the sails are left further out to get the best performance.

Moving at an angle to the wind does not do much to get a person where they are going if they need to go straight into the wind, if this is the case then the sailor would need to perform "tacks", turns in the boat in order keep perpendicular to the wind and get where you need to go.

The picture on the right demostrates the use of tacks and the position of the main sail as your direction changes compared to that of the wind.

Apparent Wind vs True Wind
Southbeach sailing
Apparent wind is something that confuses most sailors and is probably the most difficult part of sailing to master. Apparent wind is the wind that a person in the moving boat feels. It is caused by the movement of the boat and the addition of the wind created by nature or the true wind. The true wind is what a sailor needs to know in order to adjust the sails to navigate the boat. The problem is that you cannot simply measure the true wind from the moving boat nor can you tell from the difference in measured wind on the deck and the direction the boat is moving in the water, because the water is usually moving as well. In smaller boats it is fairly easy to "feel" for the best angle and sail adjustments as there are imediate responces in the movement of the boat.
The apparent wind is easy to diagram and explain. The pictures to the right are all basically vecter addition problems where the apparent wind is the sum of the true wind and the wind caused by the boat speed. This is pretty simple from this view but when you are on the boat you can only tell where the apparent wind is and you have to estimate what the exact heading of the boat is.

It is even worse when the boat is moving downwind. In these cases it is very dificult to estimate the heading and true wind since a slight change in the true wind can cause a huge change in the apparent wind. The following pictures can prove this.

Sailnet.com
Here a 16 degree shift in true wind can make a 28 degree change in apparent wind!

This is why it is more difficult to navigate while moving with the wind.

Sailnet.com
Ways to find true wind
There are a few ways to actually find the true wind. The most common is to just turn the boat until the sails begin to luff and steer themselves to the center of the boat. then you know the exact true direction of the wind. However this can be aa large waste of time sinse it will probably bring the boat to a near hault. The best way solve the problem is by experience. An experienced sailor should be familiar with the effects of the direction of the wind and boat to make adjustments based on how the sails feel.
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