What's the difference between "available credit" and "current balance"?

It says my available credit is $78.00 (credit limit $500.00) and current balance $58.50. Does that mean I have no money or 558.50? Can I use my credit card at all at this point?|||It means that the amount of credit that you can use right now is 78 and you currently owe 58.50 you might have a hold or charges pending of 363 but for sure you can use 78