Body language can have different meanings across cultures. Nodding the head means yes in most Western cultures but no in parts of Greece and Turkey. Making eye contact is encouraged in North America and Europe but considered rude in most Asian countries and parts of Africa. Gestures like thumbs up, peace signs, and OK signals can have positive, negative, or completely different meanings depending on the region. It is important to be aware of these cultural differences in body language to avoid misunderstandings.