Wallet

"As you may have noticed already, this application is a web application and runs in a browser. A connection is established to a trusted node in the network that serves as a gateway to the rest of the ecosystem.
Wallet Security

Rest assured that our servers do never have access to your funds because none of your private keys ever leave your browser. Instead they are encrypted with your pass phrase and are stored in your local browser’s database. Hence you should make sure to have a proper Backup to not lose access to your funds on computer malfunctions or browser crashes.
Wallet Management

Furthermore, the user interface is capable of carrying and accessing several separated wallets each containing possible several accounts and corresponding funds. You can add, backup, and switch existing wallets in Settings->Wallets."