Not understanding a word at my doctor's appointment

(Chapter 15 Medical Appointments and its Challenges in my book)

Today I went to my primary care doctor's office for a physical. The medical assistant said the word “demographics” and I wasn't sure what it meant. Then she handed me a paper and I looked at it and I saw the words “patient demographics”. I figured out that was the only section that she needed me to fill out. I still don't know what demographics meant but at least I was able to complete the task.