careunit type in transfers table

Could you tell us more about what the care unit types are, please? For example, what does a "Medicine" care unit mean? Other names are just as confusing: PACU, Med/Surg/GYN, Observation, Nursery - Well Babies.
Also, what does it mean when the care unit type is empty?

                                                                          Cardiac Surgery     Cardiac Vascular Intensive Care Unit (CVICU) 
                                      585397                                            18096                                            16966 
                                  Cardiology                  Cardiology Surgery Intermediate                         Coronary Care Unit (CCU) 
                                        2456                                             4718                                            11385 
                        Emergency Department                 Emergency Department Observation                              Hematology/Oncology 
                                      661053                                            85815                                            37522 
            Hematology/Oncology Intermediate                                 Labor & Delivery                                         Med/Surg 
                                       12008                                            24038                                            49926 
                                Med/Surg/GYN                                  Med/Surg/Trauma               Medical Intensive Care Unit (MICU) 
                                       27993                                            28112                                            22314 
               Medical/Surgical (Gynecology) Medical/Surgical Intensive Care Unit (MICU/SICU)                                         Medicine 
                                       10391                                            17083                                           150908 
                         Medicine/Cardiology                 Medicine/Cardiology Intermediate              Neonatal Intensive Care Unit (NICU) 
                                       46447                                             7353                                            29363 
                          Neuro Intermediate                                   Neuro Stepdown  Neuro Surgical Intensive Care Unit (Neuro SICU) 
                                        3715                                             1786                                             2488 
                                   Neurology                            Nursery - Well Babies                                      Observation 
                                       41183                                            67664                                             4604 
        Obstetrics (Postpartum & Antepartum)                            Obstetrics Antepartum                            Obstetrics Postpartum 
                                       16554                                             1471                                             4281 
                                        PACU                                       Psychiatry                       Special Care Nursery (SCN) 
                                       26459                                            13971                                            11614 
                                     Surgery             Surgery/Pancreatic/Biliary/Bariatric                                   Surgery/Trauma 
                                        9575                                             9157                                            20667 
               Surgery/Vascular/Intermediate              Surgical Intensive Care Unit (SICU)                                 Thoracic Surgery 
                                        9381                                            15308                                             3327 
                                  Transplant                              Trauma SICU (TSICU)                                          Unknown 
                                       31529                                            12342                                              150 
                                    Vascular 
                                       32965 

Thank you!

Start by reviewing the transfers table and the listed careunit values, including the empty and Unknown cases. Determine the intended explanation for each category from the project’s available context, then document what the named care unit types and empty values mean. Done means the confusing values in this issue have clear explanations.