A question about Vitamin C

[windwalker]

Hi all. Does anybody know what the difference is between Ester-C and Buffered Vitamin C? I saw both at the vitamin store (both were from the same company) near me and the employee was so busy I didn't ask. Sooooooooo, hoping someone may know what the difference is if there is any. The labels looked like they had the same ingredients. Thanks!
Dawn