In Europe, for example, people from the south are usually more of a kissing and hugging kind, while northerners like a good handshake. The most familiar and natural way of greeting in most countries in the world is very simple: the handshake.
Depending on the country, deciding how to greet is not as simple as it may seem. It may depend on the level of familiarity (is the person your friend, a family member, an acquaintance or just a stranger?) and even on your sex. In Spain, for example, you would kiss anyone on both cheeks if you are a woman. Among men, they would usually share a handshake, unless the level of familiarity is very high (family members or really close friends). Similar situations would happen in Italy, France and Latin American countries. In Asian countries, they like to keep their personal space. In Japan, they bow. In China, they shake hands or just nod.
Greeting each other is an automatic gesture, sometimes even difficult to control. Therefore, authorities have been warning about the dangers of doing it right now and recommending alternatives. New creative ways of greeting have emerged in the last few days, such as elbow bumps or leg shakes. The old-fashioned waving with your hand from a prudent distance has also been very popular these days. World leaders such as Angela Merkel, Emmanuel Macron and even Donald Trump have borrowed the traditional ‘namaste’ greeting from India.
Even if nowadays the most natural gesture for the majority of the Indian population is the handshake, the namaste greeting remains part of their culture. Far from being upset because of this cultural borrowing, most Indian people feel indifferent, positive or even proud that the namaste greeting is being used by international leaders.