The Evolution of Sailing

Square sails compared to triangular sails
The very first sail boats created were made with square sails but have you ever wondered why we switched from square sails to triangle sails. As you might imagine, square sails have a larger area then triangular sails therefore they catch more wind but why do triangular sailed sailboats travel faster then square sailed boats. Well the answer is, they do and they don't. square sails do travel faster when going directly downwind  but when approaching closer angles to the wind, the triangular sails become more effective. Now this works because the triangular sails make a foil, like the wing of  plane and converts the sideways motion of the wind into forward motion better than their square counterparts.
One of the other main differences is that when both types of sail boats go into the wind triangular sailboats can go within 30 degrees of the wind on either side whereas square sails can only sail within 80 degrees of the wind on either side making for slow progress when going upwind. Although the reason for this was unknown when triangular sails were first invented, it is now known that the triangular sails create a low pressure zone on the front side and a high pressure area behind it, making it able to sail extremely close to the wind


Flying sailboats
Well sailboats don't actually fly but with a somewhat new technology called hydrofoils enables the boats to lift themselves out of the water. Hydrofoils are underwater wings that sit deep underwater and push the sailboats out of the water when they reach a certain speed. The function very similar to the wing of a plane and are shaped in the same teardrop shape which creates lower pressure above the foil and higher pressure below the foil which in turn generates upward lift, pushing the haul of the boat out of the water. Now you may wonder why the point of doing this is other then making the boat look cool. Well hydrofoils greatly reduce the drag against the water by removing the whole haul out of the water and only leaving small wings in the water causing very little drag.If you don't believe me, the current speed record for sail boats is held by a hydrofoil travelling at 75 mph. But how is that possible when the wind isn't even going that fast. well its done by sailing faster then the wind.
https://www.youtube.com/watch?v=sZVIj5TUSKE

Sailing faster then the wind
Sailing faster then the wind is a phenomenon that takes place when a sail powered vehicle sails faster then the speed of the wind. Surprisingly this cannot happen when it is sailing downwind but normally only happens when the boats is sailing nearly perpendicular to the wind. Sailboats can go around 2 times
the speed of the wind whereas iceboats can go up to 5 times the speed of the wind. They do this by using the resistance of the surface they are on to convert the sideways motion into forwards motion, and travel faster then the wind and it is possible again because the low pressure on one side of the sail and high pressure on the other side of the sail with the addition of the forward momentum creating more pressure thus pushing it faster