Duration of med school differs from country t country. I study at a European med school.
MED SCHOOLS IN MY COUNTRY (and most of Europe I believe)
My med school lasts for 6 years; 2 pre-clinical and 4 clinical which basically means that we get to go to departments and work with patients from 3rd year on, before that we only get to shadow on different departments (I was in ER).
After 6 years you graduate and get an MD title and you become an intern which lasts for 6 months to 2 years, depending on when you take the exam and whether your wished residency has openings. After the exam, you apply to residency and if you get in you work as a resident for 4-7 years, depending on the residency. When you finish residency, you can then become an attending. You can also work on research and Ph.D. during the residency.
US MED SCHOOLS (as far as I know)
In the US med school lasts 4 years, and then you match into residency programs which as far as I know also last 3-7 years, depending on the specialty. After residency you can also apply to fellowships so subspecialize in your specialty.