The national currency is the Tunisian dinar TND. As of April 2011, 1 USD = 1.363 TND. Typical banknotes are in the values of 5 green, 10 blue or brown, 20 violet-red, 30 orange, and 50 Dinars green and purple. The Dinar is divided into 1000 Millemes, with typical coins being 5 Dinars Silver with copper insert, 1 Dinar large silver color, 500 Millemes 1/2 Dinar: smaller silver color, 100 and 50 Millemes, large brass, 20 and 10 Millemes smaller brass and 5 Millemes small aluminum. It is prohibited to bring dinars in and out of Tunisia, so you have to change your money locally.
Prices are typically marked in dinars and millemes, with a decimal point like: 5.600 or 24.000 or 0.360 sometimes with TND as a label like TND85.500. Markets typically sell items by the kilogram. So tomatoes may have a sign "480" on them which means 480 millemes per kilo. Good cheese will be marked something like 12.400 or about $10 a kilo. Most self-serve supermarkets expect you to put your purchases in supplied plastic bags and then bring them to the nearby scales where a worker will weigh them and apply a price sticker.