Before The Wind is defined as a heading similar or exactly the same as the direction in which the wind is blowing. It can also be described as having an angle of ~0° off the wind.
Before The Wind can be used to describe the heading of a ship - I.E. the ship is heading in the same direction as the wind.
When describing the position of an object, the term used is "Downwind". If an object is Downwind of the ship, the ship must turn exactly in the same direction as the wind is headed in order to reach that object.
If the wind is blowing from east to west, as occurs often in the Caribbean, Before The Wind would be directly West (W). Of course, since wind direction tends to change, the direction of Before The Wind changes with it.
While it may seem that sailing Before The Wind would be the best way to gain speed for any ship, this is not truly the case, especially for Fore-And-Aft Rigged ships.
Square Rigged vessels will usually perform rather well at this heading. However, when doing so, the wind first hits the aft-most sails, and has to move around them to reach the next set of sails, becoming less potent in the process. By the time the wind moves around to reach the fore-sails, it can exert little power on them. As a result, Square Rigged ships do get a good push forward, but not as good as when the wind comes in slightly to one side of the ship, in which case all sets of sails can receive at least some of the wind at full potential. So while Square Rigged ships can still sail fast at this heading, they perform a little better at headings such as Running Broad Reach or even Broad Reach, depending on the exact size and configuration of the sails.
Fore-And-Aft Rigged ships are not designed to utilize winds coming from aft. Instead, they perform much better when the wind is coming from the side, even perpendicular to the ship's hull. While the push of the wind will still generate forward motion at Before The Wind, these ships prefer sailing at Broad Reach to Beam Reach, in order to achieve their best speeds.
As a result, Before The Wind is considered a good escape angle for larger ships. Smaller vessels may not be able to chase them in this direction. This is especially true because the maximum speed of large Square Rigged vessels is much higher than that of smaller vessels (Square Rigged or otherwise).
Sid Meier's Pirates! (2004)Edit
In Sid Meier's Pirates! (2004), Before The Wind is considered a very comfortable angle for all ships larger than Brig Class. In fact, the larger the ship, the more accustomed it will be to sailing in this direction. Merchant Galleons, the largest ships available, seem to sail very quickly at this heading, with a very high top speed considering their huge size and mass. Although such ships generally prefer Running Broad Reach to achieve maximum speed, it is much easier in this game to keep yourself oriented with the wind than slightly off it, making this a preferred heading for large-ship combat, especially when utilizing the Snaking Chase maneuver, in which one ship stays ahead of the other while turning occasionally to bombard it.
Small Fore-And-Aft Rigged vessels, on the other hand, do not perform too well at this heading. While their small size and good overall speed help maintain reasonable sailing properties at this heading, they will feel much more comfortable keeping at least a 45° angle to the wind (Broad Reach) or more, in order to maintain high maneuverability and speed. Pinnace Class ships, in particular, are noticeably less agile when sailing at this heading, which is almost 90° off their Best Point Of Sailing (Beam Reach). Nonetheless, all Fore-And-Aft Rigged ships can still produce sufficient forward motion to keep sailing Before The Wind, though they will never catch a Square Rigged vessel running at this heading.