How to greet in English.

Hello
"Hello" is used widely in many countries to greet people.

Hello can be used:

• To greet everyone in any situation. 
• To greet a group of people. 
• To greet during handshakes and introductions. 
• To greet casual friends. 
• To greet colleagues and customers. 

Hi
"Hi" is used as a friendly greeting.

Hi can be used:

• To greet friends. 
• To greet people intimate and close to you. 
• To greet people in casual, fun filled surroundings (like family events, parties,) 
• To greet new people during friendly, casual introductions. 

"Hi" is used widely in American English, to attract a person's attention.

Good Morning
"Good Morning" is used as a formal or respectful greeting.

Good Morning is used:

• To greet colleagues, seniors at work place. 
• To greet a group or team of people. 
• To greet a group of listeners at a speech. 
• To greet new people during formal, business introductions. 
• To greet customers. 
• To greet elderly people. 
• To greet during all official, formal settings. 

"Good Morning, Good Afternoon, Good Evening" are formal greetings used at different times of the day.
"Good Night" is a parting farewell message. It is used to say farewell after sunset and before going to sleep.

Examples:

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