You are expected to follow the CSE departmental lab and shared system use policies. These policies are in place to help keep the systems running well for everyone and to provide fair access to everyone. These policies are not meant to be an exhaustive list of everything you should do or not do; you should also use "common sense" and "basic social graces".
Most of the policies are in place because the departmental equipment needs to be shared by many people. Some policies are meant to provide everyone fair access to the equipment. Other policies are to address problems that have come up in the past.