I've known for a while that some people avoid shaking hands with people of the opposite sex. I don't know whether it's purely based on religion, nationality, or whether personal preference also plays a role.

Are there some countries in which I shouldn't offer to shake hands with people of the opposite sex, even if I am socialising with them? If so, are there substitutes for hand-shaking?

closed as primarily opinion-based by user141, Dirty-flow, LessPop_MoreFizz, VMAtm, user1712 Dec 19 '13 at 15:53

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