When first registering a Bitcoin wallet based on Counterparty you will receive a password composed of 12 (24) random words named the seed. This represents a higher security measure. The seed will be used to generate the private key to your wallet.
Write this down and keep it secure!!! Should you lose this you will not be able to have access to your currency and tokens and those could be lost forever. If the key gets in the posession of somebody else, they will be able to gain access to your wallet.
Before using the wallet it is wise to first make sure you have correctly marked down the password. If not, it is best to generate a new wallet and to pay more attention when writing down the password.
Afterwards you will be able to use the password in any type of wallet when want to access your currency and tokens. This key (the password) is encrypted and acts like a highly secure bank account. All owned currency will be connected to this password.