### Instruction: What is the best bidding system in duplicate bridge?
### Response: Bidding systems in bridge allow the partnership to communicate the strength and various characteristics of their hand to arrive at an appropriate contract. A good bidding system should be descriptive, accommodate many different hand types, and account for interference from the opponents. There is no clear best bidding system as they all have advantages and disadvantages but 2/1 (two-over-one) is accepted to be the standard that people use. The reason is that it can describe many hand types efficiently through natural bidding, it is easy to learn and understand, and handle interference from opponents.