Greeting and Responding People:
Greeting refers to welcoming someone with certain words/phrases or a specific action. When we meet someone for the first time we greet by shaking hands and saying "How do you do?" or "Pleased to meet you." or "Nice to meet you" or "Nice to see you" or "Nice to have you on the phone" (through phone)
Generally with people we know well, We greet by just saying 'hi' or 'hello'
Here are some expressions you can use to greet and respond people in English Speaking:
Greeting [Hi, hello.] Responding [Hi, hello.]
Greeting [Good morning, good afternoon, good evening.]
Responding [Good morning, good afternoon, good evening.]
How are you doing?
How are you doing today?
How are you going?
I'm fine thank you (thanks)!/ I'm doing good (thanx)!/ Thank you (thanks)/Not bad.
Additional: How about you?/And you?
Greeting: [How do you do?] Responding: [How do you do?]
"How do you do?" isn't actually a question, it simply means "Hello".
David: Hi! My name is David Wilson, the Supervisor.
Mark: Hi! This is Mark Brown. Nice to meet you, David.
David: Mark, I'd like to introduce you to Jason, the Engineer.
Mark: How do you do?
Jason: How do you do?
David: Hi! Mark, How are you today?
Mark: I am fine Thanx. How about you David?
David: I'm good.