bandwidth usage?

will someone please explain what this means???

Monthly Bandwidth Utilization Surcharge: Average Bandwidth
0 - 128Kbps free
128 - 192Kbps 10$
192 - 256Kbps 30$
256 - 320Kbps 75$
320 - 384Kbps 100$

I would venture a guess that you can choose how fast you can download, and you pay on a sliding scale.

"0 - 128Kbps free" = upto 16k/s is free, any more will cost you.