Is canola oil a form of vegetable oil?
If you see "vegetable oil" on the bottle, it's usually canola--the least expensive, lightest-colored, most flavorless oil they can get their hands on. (And in this case, "most flavorless" is a good thing; there are times you don't want to taste the oil, like if you're making brownies.)
Canola oil is pressed from tiny canola seeds produced by beautiful yellow flowering plants of the Brassica family. It can be used in any recipe calling for vegetable oil.
Cabbages and cauliflower are also part of the same botanical family! Canola was bred naturally from its parent rapeseed in the early 1970s. Canola, however, is NOT rapeseed - their nutritional profiles are very different.
Along with olive oil, it is one of the most beneficial oils in its effect on good and bad cholesterol.
Most of this info is from the Snopes article debunking the myth of Canola's toxicity. See the related link below.
Olive oil is sometimes less costly and is definitely healthier for non-baking. Conola oil is better for baking than olive oil.
Does vegetable oil cause rust?
Vegetable oil does not cause rust. It is slightly acidic, its similar to a lubricant and it can prevent rust.