There are 2 types of smoking, Hot and Cold. These processes are 2 completely different methods for preparing food. Hot smoking cooks the food, whilst Cold smoking is a part of the process designed to cure food that will, in most cases, be cooked at a later stage. No one can be sure of when it all started, but it was probably discovered, by accident, sometime during the Stone Age. In the case of Hot Smoking, you can imagine a group of hunters bringing meat back to their cave and hanging it above the fire they used for warmth. Cold Smoking/ Curing may have been discovered in this manner... picture freshly caught sea fish, being filleted on site and then left to soak in a rock pool for a few hours, before being returned to the cave where it was hung further away from the fire, possibly nearer to the roof, where the smoke gathered. In both scenarios, man might have been pleased with the resulting flavour (he may even have been given a hearty smack on the back, known as a pat, from the people sharing the meal, to show their approval). He may have also noticed, in the case of the fish, that the food lasted a lot longer, without spoiling. As with most men, he more than likely got impatient, whilst waiting for his meal and ended up by first moving the meat closer to the fire (Barbecuing) and finally, by throwing meat directly onto the fire (Grilling).