Man greeting Man - Men usually greet one another with a light handshake.  Handshakes may linger and sometime lead into hand holding.  This is purely a sign of friendship.

Woman greeting Woman - Women greet each other in a similar manner to men.  Handshakes are the common.

Greetings between Men & Women - There is little to no touching between men and women during greetings in public.  Women may extend a sleeve-covered wrist or hand to be shaken.  Always wait for the woman to initiate, if at all.