Vienna has an exellent public transport system of trams, busses and subways. Since it's a large town and there's not much (free) parking space available, public transport is the easiest and cheapest way to get around. You can get a wide range of tickets, including tickets valid for an hour (1,5 EUR), 24 Hrs. (5 EUR), 7 days (12.5 EUR), etc. The advantage of an 8 day-ticket is that it doesn't have to be 8 consecutive days. It doesn't even have to be 8 days, you can use it for more than one person at a time, for instance, 2 people can travel on it for 4 days. All these tickets are valid in the entire Vienna district, in all busses, trams and subways.