The United States Medical Licensing Examination (USMLE) is a big test that people have to take in order to become doctors in the United States.
The test is divided into three sections, or steps, which doctors have to take at different times during their training. The first step is usually taken after the second year of medical school, the second step is taken during the fourth year of medical school or during the first year of residency training, and the third step is usually taken during the second or third year of residency training.
The test is really important because it helps to make sure that doctors are knowledgeable and skilled enough to take care of patients. The test includes questions about lots of different medical topics, like anatomy, physiology, pharmacology, and more. It's a really tough test, but if someone passes all three steps, they become a licensed doctor in the United States.