Common sorrel has been cultivated for centuries. The leaves may be puréed in soups and sauces or added to salads; they have a flavour that is similar to kiwifruit or sour wild strawberries. The plant's sharp taste is due to oxalic acid. It's a good ingredient for a salad, but as the flavour is quite strong it's an idea to tear the leaves into smaller pieces and not use too many.
It's one of those herbs that you are unlikely to find in a supermarket so you would probably need to grow this yourself.