One of the lesser known facts about sailing is that the power of the wind can actually be harnessed to sail in a direction against the wind.
It can also be harnessed to sail at a speed exceeding that of the wind, even if the water is relatively calm.
What is even less known, for obvious reasons, is that you can do both at the same time—meaning you can reach speeds up to double that of the wind!
Despite what logic may dictate, this does not actually contradict any laws of physics.
The trick is to make use of all three dimensions of space when sailing, the most obvious one being the direction that the wind velocity is orientated in. If this is the only dimension you exploit, however, you will only be able to reach the speed of the wind and not exceed it.
If you also make use of the crosswind by tacking the sail then, in principle, it becomes possible to travel at double the speed of the wind.
To be able to sail against the wind you will also need to harness the power of the water underneath the sailboat by using the keels, rudders, and hydrofoils which can be seen as the 'sails' under the water.
One should therefore be able to sail against the wind (or in any direction) at speeds faster than the wind, if you tack the rudder or other hydrofoils as well as the sail.