When I looked into this, it was the area and value of the abode. It applies to everyone, though full-time students can get an exemption. If you live by yourself, you can get a 25% discount. I reckon that if your landlord is paying it for you, it is folded back into the cost of the flat (because its a good chunk of change).
There was a website that gave specific amounts for each specific address - it wasn't hard to find doing a google search (I think using terms Council tax band A).
The flat that I am renting (that is the first floor of a 3 story abode) must be valued at less than 40,000 pounds because I am in band A.
It works out to 80 some pounds per month, 72 with my 25% discount.
Not sure if it is paid on a monthly, 3-month or 6-month basis though....