Centralized vs decentralized crypto wallets
A wallet is the medium that stores a user’s private keys that grant him/her access to their digital tokens.
The private key is the combination of characters that is generated by cryptography and acts as a digital signature of its owner.
Multi-signature is essentially a signature that requires the simultaneous presence of more than one unique key to confirm a transaction or access the resources.
Double spending occurs when a digital currency is replicated and spent twice.