A personal wallet is an M-of-N multi-signature digital asset wallet. However, the client only requires a single signature in order to create a transaction. QD is taking care of the other signatures on behalf of the client. 

A shared wallet is also an M-of-N multi-signature digital asset wallet. The shared wallet signature holders are other QD users who are chosen by the wallet owner.

Both wallets are capable of M-of-N multi-signature support for the utmost in security and safety as it will provide:
Dividing up responsibility for possession of cryptos among multiple parties.
Avoiding a single point of failure, making it substantially more difficult for the wallet to be compromised.
M-of-N backup where the loss of a single seed doesn't lead to loss of the wallet.

* QD is currently supported 2 of 3 multi-signature and will provide more options on the number of the M and N soon.