What are tannins? They actually come from the skin, seeds + stems of the grape + are typically more pronounced in full-bodied red wines. Although, there are white wines that may have tannins from being aged in oak barrels. The science can be overwhelming, but I like to describe tannins as the dry substance or feeling at the back of your throat that can sometimes taste chewy when you drink a full-bodied red wine. Tannins can definitely add complexity + depth to a well aged wine or add bitterness + astringency.
Tannin has also been shown to provide many benefits to your health, so go ahead + pour a glass!