Explain One Hand Clapping in Buddhism?

Answer 1

"What is the sound of one hand clapping" is a well known Zen Buddhist Koan. Koans are questions whose answer cannot be arrived at through analytical mental processes - you can't think your way to the right answer.

The only route to the answer for a Koan is the instantaneous appreciation of the qustion at an intuitive or instinctive manner.

Resolving Koans trains the Zen student in this non-analytical mental process.

This means that simply telling you an answer to the Koan is a useless endeavor. There are books and papers written on the meaning of many Koans but none of these contain your answer.