Repeated studies prove that babies need to be touched to grow and thrive and that older people are healthier both mentally and physically if they are touched.  Some people are more comfortable with touch than others.  Some people shake hands in greeting but otherwise don’t like to be touched at all, except by family members or close friends.

Most parts of North America allow opposite sex couples to hold hands or walk arm in arm in public but frown on the same behaviour in same sex couples.  People in Asia, the Middle East and South America have the opposite expectation.  Male friends or female friends can hold hands or walk arm in arm, but it is slightly shocking for opposite sex couple to touch in public.  In Iran and Iraq, handshakes between men and women are improper.