As I discussed above, Residency is a 3+ year training program in a medical specialty. The first year of training after medical school is called internship, or more commonly it is called first year of residency or PGY-1 (PostGraduate Year-1). The following years are called PGY-2, PGY-3, etc. The training that is done after a residency (in a subspecialty) is usually called a fellowship. Much of what you will learn in your chosen specialty will be learned in your residency.
It's hard to believe that, after 12 years of school, 4 years of college and 4 years of medical school, there is still so much to learn. The first 20 years of school are the foundation and the tools you will need to learn your specialty. During your residency you will learn medicine by caring for patients with a variety of diseases. The more patients you care for, and the more disease and variations of disease that you see and treat, the more proficient you will become. The knowledge obtained from patient care is supplemented with lectures and conferences.
There are so many different residencies, but generally the first year of residency (internship or PGY-1) is spent either rotating through different specialties or rotating to different areas within one specialty. In my case I spent the year rotating, in 1 month intervals, to the ER, General Surgery, Internal Medicine, Intensive Care Unit, Orthopedics, Pediatrics and OB/GYN. After the first year much more emphasis is placed on your own specialty.
A typical day in residency starts around 7AM. First you see your patients prior to "rounds" to check on the results of diagnostic tests, to see how they are responding to therapy. Next are "rounds" with your team. A team usually consists of several interns, a upper level supervising resident, and an attending or teaching physician. They take care of a specific group of patients. "Rounds" mean you walk around to each patient to discuss his or her care. Suggestions on further diagnostic tests and treatments are the usual topics of discussion. After rounds you may return to see some patients in more depth, do whatever procedures need to be done, talk to the patient's private physician, etc.
Usually there is a lecture or conference at some point in the day. After lunch new patients are often admitted to your team. You will need to do a history and physical exam. Then write their admitting orders. These are written instructions about which tests, medications, etc. are to be given for this patient. At the end of the day you "sign out" to the team that is "on call" that night. This is done to tell them about either all your patients or the ones that may run into trouble that night. At home it is important to continue to read about medicine, especially at this point in your career. However, fatigue plays a big role and you often need recovery sleep from your night on call.