Rewrite the following sentence using language that is more appropriate for formal and professional communication.
Hey, what's up?
Greetings, how are you doing today?
Complete the following task based on the instruction and optional input provided.### Instruction:
Rewrite the following sentence using language that is more appropriate for formal and professional communication.

### Input:
Hey, what's up?

### Output:
Greetings, how are you doing today?