Product Advertising API
Developer Guide (API Version 2013-08-01)

General Differences

Amazon marketplaces are localized by language, custom, and formatting conventions. In addition, the locales may vary, as described in the following table.

Difference Description
Items for sale The selection of DVDs, for example, sold in the JP locale are different than those sold in the DE locale. The same is true for books. Not only are the languages of the books different, the selection of books varies by locale.
Customer feedback Amazon encourages customers to share their feedback on items, sellers and merchants. Customer reviews are restricted to the locale in which they are entered.
Sellers and merchants Sellers and merchants can do business in multiple locales but they don't have to. As a result, items from a seller might be available in only one locale. The largest merchants, beside Amazon, are available in the US locale only.
Customer accounts Customer accounts are restricted to a locale. A customer can create accounts in every locale.
Item identifiers Item identifiers, such as ASINs, are unique to a locale, that is, the same ASIN value can refer to different items in different locales.
Availability of some response groups The availability of some response groups, sort parameters, and search indices varies by locale.