Reverse flow smokers

I'm looking to build myself a new smoker over the winter to keep me busy.
i'm looking to make an offset using an oil barrel, but i've seen a few people talking and making reverse flow smokers and i'm wondering what the benefit of reverse flow is
i'm looking to make an offset using an oil barrel, but i've seen a few people talking and making reverse flow smokers and i'm wondering what the benefit of reverse flow is
