Cultural differences in nonverbal communication can lead to confusion. Facial expressions, gestures, eye contact and conversational distance have different meanings across cultures. For example, smiling at strangers is considered unusual in Russia but common in the US. The "OK" gesture means money in Japan but approval in the US. Showing the sole of one's foot is insulting in some countries but not others. Cultural sensitivity is important, as behaviors like eye contact, physical contact between friends, and the expression of emotions vary significantly depending on cultural norms.