I found the grocery store only has boxes labeled oatmeal now not rolled oats.
You have to go to a health food store to find something labeled "rolled oats".
But, "Quaker Old fashioned Oats" is rolled oats from what I could find.
Joy of Cooking was kind of vague. I googled them and found:
Oatmeal is ground oat groats (the seed after the husk is removed). It can also be steel-cut oats, crushed oats, or rolled oats (steamed oat groats rolled flat).
Quick oats are oats have been cut into pieces before being steamed and rolled into thinner flakes. They are are popular for oatmeal cereal, but old fashion oats (rolled oats) are better for cooking (e.g. toppings for apple crisp, oatmeal cookies) because of their thicker texture and superior flavor.
Instant oatmeal is pre-cooked and dried, usually with sweetener and flavouring added.

Cooked oats as a breakfast cereal is called oatmeal in the US, porridge in Scotland or Stirabout in Ireland. Porridge can be made with Rolled oats, steelcut oats or pinhead oats. Pinhead oats are coarse stoneground oats resembling steelcut oats.

Food Size oz kCal./
3.5 oz
Carbs Fat Protein Fiber Sugar
Oatmeal Quick oats 1/2 Cup 1.38 356 67% 6% 13% 10% 0%
Oatmeal Old fashoned 1/2 Cup 1.41 372 68% 8% 13% 10% 3%
Oatmeal Instant Maple And Brown Sugar 1 Pkt 1.52 369 74% 6% 9% 9% 34%
Oatmeal Bread 1 Slice 0.88 258 48% 4% 8%
Oatmeal W/ Raisins Cookies 4 Cookies 1.83 467 69% 19% 6%
Other Cereals
Quick oats and Old Fashioned oats are complex carbohydrates which take longer to break down than simple carbohydrates so you feel full longer and will be less likely to over-eat throughout the day. They have a low glycemic index which is good.
Instant Oatmeal has a lot of sugar and is not a good for you.

JoyOfBaking.com/OatmealCookies.html notes:
Rolled oats were first produced in 1877 by The Quaker Mill Company and are known for their distinctive cardboard canister with its red, white and blue label. By 1884 the Quaker Mill Company began selling their product, calling it "Quaker Oats". Incidentally, Quaker Oats is said to have been not only the first packaged food in America but also the first product to be mass marketed in the United States. And speaking about Oatmeal Cookies. The first oatmeal cookie recipes contained just one half cup of oatmeal. The recipes that we see today, that are loaded with oats, are adaptations of a recipe first developed by The Quaker Oats Company during the Second World War. That recipe also used vegetable shortening instead of butter, which was in short supply. So if you see recipes today calling for shortening you now know where that originated

Oatmeal & Porridge
About Oatmeal @ Apple Crisp Recipe - Joyofbaking.com

last updated 15 Oct 2011