Wine is a drink that heals 11 Hits and lowers Attack by 3 levels when consumed.
Wine can be very useful for pures. If one drinks enough alcohol so that their Attack level is under 8, then they can attack the dummies in Varrock and gain Attack experience without getting any Hits experience. "Wining" a pure will make it so that it hits around 1-2 damage higher than regular pures of the same level, which can be very useful for three-hitting an enemy in the wilderness. It is sometimes an advantage in staking, especially when by Hits level.
Wine can be made at level 35 Cooking by placing grapes in a jug of water. This may fail, which results in bad wine. The player must then wait for the wine to mature, assuming that they have not failed. Once the player is level 70 Cooking, they will no longer fail maturing the wine.
At some point before a hidden update, wine could be drank twice, which made possible getting a half full wine jug.