As the name suggests, backsweep is the angle at which the bars bend back towards the rider, and usually ranges from 0-degrees to about 12-degrees. Some radical designs have up to 45 degrees of backsweep, but that's rare.
Upsweep refers to how the ends angle upwards from horizontal, and is a separate thing from the rise. Not all bars have an upsweep listed, but most measure between four and six degrees.