Very quickly, inmates basically have two accounts: their current account, which is like a chequing account; and then a savings account.
Offenders who earn money in the institution through inmate labour get their pay; it's a cashless process, all handled through computer. A portion of their pay cheque must go into their savings account for planning for the future and eventual release. The other portion is allowed to go into their current account.
Family members and people of that nature can send money to the institution. All of those moneys must go into their savings account, and in a fiscal year they're allowed four transfers from their savings to their current accounts, to a maximum of $500.