Flavoured Vinegars tend to be wine vinegars steeped in herbs, such as tarragon, basil, savory, thyme, bay leaves, rosemary or other aromatics like lemons, shallots, or with salt and /or sugar. Tarragon vinegar is really good and popular in making sauce Béarnaise.
Dowell, P., Bailey, A. (1980) The Book of Ingredients, Dorling Kindersley. ISBN 0718119150.