When being introduced or greeting someone, men say Sawatdee-krap and women say Sawatdee-kah.
Thais greet each other with a "wai." Foreigners are not expected to initiate the wai gesture, but it is an insult not to return the wai. If a wai is not offered to you, shake hands with men and smile and nod to women. A Thai businessperson may shake hands with a foreigner. Offer a wai only to a person of equal or greater status. Subordinates should offer a wai first.