In most of the Middle and Far East, it is considered an insult to point your feet (particularly the soles) at another person or to display them in any way, for example, by resting with your feet up.
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the Editors of Publications International, Ltd.. "13 Examples of Good and Bad Manners Around the World" 21 September 2007. HowStuffWorks.com. <http://people.howstuffworks.com/13-examples-of-good-and-bad-manners-around-the-world.htm> 16 May 2012.