What are lymph nodes and is a lump behind the ear dangerous?

7:23   Clinical Examination of Head and Neck Lymph Nodes - Clinical Skills - Dr Gill 5:53   Examination of the Lymph Nodes - Clinical Examination 4:19   Lymphnodes (a) 1:46   Lymph Node Examination- Head and Neck 0:41   Examination of the lymph nodes of the head and neck 1:14   When to see a doctor about swollen lymph nodes 3:15   When should I see my doctor about a swollen lymph node? 3:40   Swollen Occipital Lymph Node: What's Behind It? 7:13   LYMPHOMA After Ignoring 6 WARNING Signs 0:43   Lump in Back of Head for 1 month in 16 y.o. Boy: Point-of-care Ultrasound Evaluation 3:22   What causes swelling of lymph node near the ear in a young female? - Dr. Satish Babu K 10:53   Swollen Occipital Lymph Node: Causes And Treatment 2:03   Have an Infected lymph node? Here is what you need to know!