CRNA? Certified Registered Nurse Anesthetist (like an NP, a CRNA has at least a Master's Degree (soon minimum will be doctorate) and practices advanced decision making and skills
LVN? Licensed Vocational Nurse
LPN? Licenesed Practical Nurseh
these titles are for the same scope of nurse who does much of what an RN does, depending on facility. The use of "V" or "P" varies by state
CNA? Certified Nursing Assistant- nurses' aides in nursing homes must be state certified.