My Dad was a SeaBee in WWII. My brother was on the USS Mispillion in 68-69. My son is a Lieutenant in the Navy. He started as a seaman in 1997. He is a nuclear guy on carriers. I served in the army. I am a landlubber. I appreciate your information. I feel richer for it.
The best angle for the wind in a sailing ship is from the side. That way you can use the most sail. (not that you can't sail with it coming from another angle). That pic only LOOKS like the flags are talking behind. The wind is coming from the side.
The best angle is not quite from the side, but a bit backwards from the side. But you can't always get what you want. Sometimes (as is the case in the picture) you've got to sail with the wind coming from about 45 degrees from the front. That is the case in the picture. All sails are too much close hauled to sail comfortably with the wind coming from the side. With the wind from the side you let the sails (more precisely the sheets) loosen a bit. I'll show some pics later, but right now I've got to help my daughter with her homework. < edit > See the image below: the boom of the sail aft (below in the pic) is pulled right in. In the picture of @gorgo2 the boom is pulled even more in. See what I mean?