For anyone that isn't aware of what fingerprinting is, here is an example.
I rob a bank without using a disguise, showing my face and leave behind my fingerprints on the door I use to enter the building.
Nobody there knows my name and so I still remain 'anonymous'.
But then the cameras and witnesses can fingerprint me based on how I look and law enforcement can fingerprint my identity from the fingerprints I leave behind on the door and counter. So then I'm caught.
If I was to use a disguise and wear gloves, I would remain anonymous and I leave only a few fingerprints behind.
In the virtual world there are many more fingerprints that your browser leaves behind that will track you and a HUGE amount of this information is sourced with javascript.