My grandfather taught me to greet the elders by touching their feet whenever I met them. A Namaste too would work many a time, but he would insist that there is no harm in giving additional respect. Though some of the rituals became modern with time.
If you shift abroad, knowing how to greet people could give a great start to your journey! Some cultures believe specifics.
In South Africa, you are expected to greet the locals explicitly in the office every day, as you see them. If you are going for lunch or tea, asking them is expected. Even in the daily walk of life, expressing greetings before getting into conversation works best, as if ‘declaring’ it! South Africans would respect you equally, if not less. They may take it as an offence if you do not greet them, though it may be unintentional!
Do you have any tale about greetings worth sharing?