"What's happenin'" is a casual and colloquial phrase typically used as a greeting. While this phrase is commonly used in everyday conversation, there are many different synonyms that can be used in its place. One common alternative is "what's going on," which has a similar meaning and can also be used as a greeting. Other options include "what's up," "what's new," and "how's it going." Each of these phrases can be used to start a conversation and inquire about someone's current state or situation. Regardless of which synonym is used, the intent is always to start an engaging and friendly conversation.
