M-of-N is one of the shared wallet management modes.
M is the number of owners' approval required to authorize a transaction. N is the total number of owners in this shared wallet. For example, if the wallet is set as 2-of-3 mode. Then each transaction will require at least 2 owners’ confirmation to authorize the transaction.
Consider the following scenario:
Suppose I am working with a company that wants to accept cryptocurrency for international trades. The company, for security reasons, would not want a single one of its employees to have access to the company wallet's password. Any transaction would have to meet the approval of more than two employees, and a total of 6 employees may need access to the company's funds.
To make this possible, I can create a 2-of-6 HyperPay shared wallet and invite everyone to join this wallet. Whenever someone needs to make an outgoing payment from the company funds, 2 confirmations are required to authorize, preventing one single employee from spending the money without the approval of another.