I'll admit it- I didn't know what a "general surgeon" did until I was well into my 3rd year of medical school. I knew that a "surgeon general" put scary warnings on cigarettes packages; but a "general surgeon"? I was lost. So here is my general overview of general surgery. Generally.
The following people who do surgery DID NOT go through general surgery training: neurosurgeons, orthopedic (bone) surgeons, ENT (ear nose and throat) surgeons, urologists, gynecologsts. They go straight from medical school into their residency specialty; though most of them will still spend a few random months on general surgery rotations as part of their training.
The following people who do surgery DID go through general surgery training (5 years) and THEN did a "fellowship" (extra 1-3 years after residency to further specialize) in a more specific field: colorectal surgeons, cardiac surgeons, thoracic (lung) surgeons, bariatric (gastric bypass) surgeons, plastic surgeons, pediatric surgeons, vascular surgeons, trauma surgeons, hepatobiliary surgeons, oncologic surgeons, breast surgery.... the list goes on.
So what does that leave to the "general surgeons" (people who complete general surgery residency and do not go on to do a fellowship)? Lots of hernia repairs, appedectomies, removing gallbladders, biopsies of everything, exicisions of skin cancers, intestine surgery, thyroid surgery... and that list goes on too.
As if that isn't confusing enough, general surgeons really are trained to do almost everything that those fellowship surgeons can do. The fellowship surgeons just have extra training; and only do surgeries within their smaller field. For example, if you live in Garden City, Kansas- a general surgeon is probably doing a bariatric surgery, followed by a colon cancer surgery, then running over to do a trauma surgery, and wrapping up her day with a pediatric appedicitis surgery. But if you live in New York City- there is a highly trained and very specfic surgeron who wants to fill her whole day with bariatric surgery; and another who wants to do all cancer surgery; and another who only wants to do do trauma stuff; ad a pediatric surgeon who shuns everyone over 18 years old.
I still think its confusing. The first "oncologic surgeon" that I met must've thought I was a jerk. I kept asking him what kind of surgeries he did; and to every thing that he said I would reply- "But general surgeons do that!!" So the way that I think about it is that general surgeons can do everything*; and going on to a fellowship just allows you to do a certain thing more often.
*General surgeons can't really do EVERYTHING. Cardiac and thoracic surgery, for example, are RAREY done by someone who hasn't done a fellowship. But pretty much everything else that I listed can be done by someone who has 'just' done general surgery residency.