When You meet and Introduce

Hello!
Hi!
Good morning! (before 12 noon)
Morning ! (casually)
Good afternoon!(12 noon to 6 p.m)
Good evening!(after 6.pm)
Hello! Pleased to meet you.
Hello! Myself Govind Arya
Hello! I’m Govind Arya.
Hello! I’m Govind Khurana. I am a senior manager here.
Hello! She is Aparna Gupta, She is a businss executive here.
Hello! Have you met our new sales representative Mr. Prakash Tripathi?