A question about "Tannins"

[Drew]

I've been drinking wine for years but only gotten serious about it for about two years now. I understand tannic acid as a natural preservative found in the pigment of grape skins and its' importance in red wines that benefit from aging. What confuses me though are descriptions..."well integrated tannins, soft tannins, polished tannins, supple tannins, ripe tannins" etc. and the ability by reviewers to translate the presence of tannins in certain wines to predict the wines aging potential. Please help clarify.

Thanks....Drew