Your regular carving pumpkin that you buy at the store is usually a Connecticut Field pumpkin. It has deep ridges and some texture to the surface, and is a bright orange in color. But pumpkins come in wide variety of colors, from white to red to orange to yellow to green (yes, it's green even when ripe). They range in size from softball-sized to those six-feet-across monsters that compete for the Guinness book.
Connecticut Field and other carving pumpkins are chosen for their hardiness in the field and during processing, and for their great carving abilities. Sugar pumpkins, however, are much smaller and have little of the ridges and skin texture. Sugar pumpkins are sweeter tasting than Connecticut Fields, and are often used for pie mix.
Pumpkins are basically winter squash, and can be cooked and eaten just like squash. Roast pumpkin is great!
If you like a sweeter roat pumpkin, here's a recipe. You should use a carving pumpkin for this recipe, as using a sugar pumpkin will casue the dish to turn out too sweet.
Sweet Roast Pumpkin
1 small (2 to 8 lbs) pumpkin or 1/4 large (8 to 15 lbs) pumpkin
1 tablespoon olive oil
Ground clove (to taste)
Ground cinnamon (to taste)
Ground nutmeg (to taste)
1 tablespoon packed brown sugar
Heat your oven to 400F. De-seed your pumpkin, and cut the pumpkin into slices about one inch thick.
Place the pumpkin slices on a baking sheet. Drizzle with olive oil and rub to coat both sides of the pumpkin. Season with salt, spices, and brown sugar. Roast for 20-25 minutes, depending on thickness of pumpkin slices, turning once.