Bitcoins are created as a reward in a competition in which users offer their computing power to verify and record bitcoin transactions into the blockchain. This activity is referred to as mining and successful miners are rewarded with transaction fees and newly created bitcoins.[14]:5–7 Besides being obtained by mining, bitcoins can be exchanged for other currencies,[27] products, and services.[28] When sending bitcoins, users can pay an optional transaction fee to the miners.[29] This may expedite the trans
