The main difference between the two is how your body reacts. When you smoke or vaporize cannabis, most people will start to feel the effects within 10 minutes and it will last about 2 hours. An edible or oils, on the other hand, can take a bit longer to take effect - for some 2-3 hours, because it has to be processed through your liver. The effects can last for 6-8 hours. There is no right or wrong method and some use a combination of the two depending on their needs. For example, if you have trouble falling asleep you may want to vaporize before bedtime. Or, if you have trouble staying asleep an oil or edible might work better for you.