Greetings to a friend or acquaintances reveals the desire to maintain good relations with the people around you.
If the greeter is an adversary, there exists the evident desire to reconcile; meanwhile, if it is a woman, it ensures that difficult projects will achieve success.
[1]1. If shaking hands with someone warmly, one is ready to take on a new project.
2. If one refuses to shake a hand, one is not ready for a project.
[2]