I've been scribing for the last year and although each program is different, here's a basic overview of what I've done:
You accompany the physician to the patient room with a tablet, (some places do computers on wheels aka COW's) and document the HPI as the patient explains why there have come to the ER. You can also document their review of systems, past medical history, recent medical visits and if they've had these symptoms previously.
After questioning, the physician will then start his physical exams. Some doctors verbalized their findings in the room as they go and others will tell you their findings when you leave the room.
You repeat this process with all the patients your assigned doctor sees.
Once the doctor has put in orders, you will check to see when labs are up and tell your doctor and update them in the chart. The same goes for x-rays that you can watch as the physician read it and point out his findings on the screen. You will also update any readings done by a radiologist for ultrasounds (that are not done bedside by the physician), MRI, CT scans an put them in the chart.
Lastly the doctor can dictate a course of Care or dictate progress note along the way basically explaining their thought process, their differential diagnosis and the patients disposition.
Scribe is great cause not only do you interact with the ER doctor but you get to see the jobs of ER techs, respiratory therapist, nurses, phlebotomists, PA's. I'm at a level 1 trauma center so each trauma is seen by an ER doc and trauma surgeon upon arrival. I get to interact with the trauma surgeons a lot and we get many transfers via helicopter and MVA's, stabbings, GSW's. All very interesting cases.
In addition I get to witness consults with many different specialties such as Ortho, Intensivists, Neuro, Neurosurg, gen surgery, Cardiology being the most frequent.
I believe med schools really like applicants with the experience as you get direct clinical exposure so you know if you can handle the blood, if you like the ER doc lifestyle and if you want to be a doctor. Every time I go to work, I know I want to be a doctor. You also gain knowledge of medical terminology such as anatomy and diseases. I feel I'm pretty good at reading chest x-rays and can identify a lot of structures and abnormalities on CT chest/abdomen such as broken rib, aortic dissection, liver lac, splenic lac, gallstones. EKG's are a whole different animal though.
Obviously every ER is different, but hopefully this gives you a good idea of the scribe job.
Let me know if you have more questions!