i discovered that my galaxy s2 device has less ram and storage than advertized

according to the Task Manager:

Ram : 837MB
System storage: 1.97GB
USB storage: 11.50GB

i expected 1GB of Ram and 16GB of device storage ! this is a ripoff ?
btw what is the difference between the system storage and usb storage ? are these logical partitions or physical ones?
are the units used supposed to refer to GIB or GB?

please post your specs if you've any galaxy s2 device