Mining is also the mechanism used to introduce Bitcoins into the system: Miners are paid any transaction fees as well as a “subsidy” of newly created coins. This both serves the purpose of disseminating new coins in a decentralized manner as well as motivating people to provide security for the system.

### Bitcoin is Secure

Bitcoin mining is so called because it resembles the mining of other commodities: What is Proof of Work? A proof of work is a piece of data which was difficult costly, time-consuming to produce so as to satisfy certain requirements.

It must be trivial to check whether data satisfies said requirements. Producing a proof of work can be a random process with low probability, so that a lot of trial and error is required on average before a valid proof of work is generated. Bitcoin uses the Hashcash proof of work. What is Bitcoin Mining Difficulty? The Computationally-Difficult Problem Bitcoin mining a block is difficult because the SHA hash of a block’s header must be lower than or equal to the target in order for the block to be accepted by the network.

This problem can be simplified for explanation purposes: The hash of a block must start with a certain number of zeros. The probability of calculating a hash that starts with many zeros is very low, therefore many attempts must be made.

### 1. The Bitcoin Bible

In order to generate a new hash each round, a nonce is incremented. See Proof of work for more information. The Bitcoin Network Difficulty Metric The Bitcoin mining network difficulty is the measure of how difficult it is to find a new block compared to the easiest it can ever be.

It is recalculated every blocks to a value such that the previous blocks would have been generated in exactly two weeks had everyone been mining at this difficulty.

### 2. Mastering Bitcoin

This will yield, on average, one block every ten minutes. One of the ways known to be effective is by reading books.