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In traditional financial systems, new banknotes are simply printed by the governments of countries whenever they need them. But digital currencies come into being differently. They are generated by computers, and this process is called mining. The essence of mining is that a multitude of computers that are not connected to each other, through a special program (a miner), solve mathematical computational problems necessary for the functioning of the blockchain of a particular cryptocurrency's network, and thereby generate new coins. Translated from English, mining is the extraction of minerals; in this analogy it is the extraction of cryptocurrencies. In slang, miners are also called diggers.

In most systems the number of units of a cryptocurrency is fixed and determined in advance. However, this rule does not always apply: in Ethereum, Ripple, Namecoin and some other digital currencies the final number of tokens is not set and can grow as the market requires. As for the issuance itself, the most well-known way of carrying it out is mining (PoW), used in the Bitcoin, Litecoin, Dogecoin networks and many others (in some systems it may be absent, and the issuance is carried out through ICO, IPO crowdfunding or forging (PoS)).

A typical mining farm is a high-performance computer with several graphics cards. At first glance it seems that everything is simple: you connect the computer to the network, configure it and watch it earn money. A cryptocurrency is a code, a set of digits and at the same time a unit of payment. Miners of digital money perform calculations using their own computing power and special software. In return they receive a certain amount of electronic money, which can be exchanged for any currency: dollars, euros or rubles. However, ordinary PCs, laptops, game consoles or mobile gadgets not only fail to provide sufficient performance, but they also cannot be used for their intended purpose during mining — the process takes up all of the device's resources.

So, what is needed for mining?
To generate coins you will need the following:
- An electronic wallet. It can be downloaded from the official resource of the developer of the specific digital currency. It is a password-protected container in which the received income will be stored.
- A software package. At present there are various mining programs available on all popular operating systems (Windows, Linux, OS X).
- Registration in an online pool of miners. Members of these communities pool their computing devices to increase the efficiency of their work. The coins obtained are divided among all participants.
- Registration in an online exchanger. It will be needed by those who want to immediately convert virtual coins into ordinary money.
- A reliable internet connection. Ideally, the speed should be at least 2 megabits per second. The higher, the better.
- A place to install the equipment. It is good if this is a basement or another cool or air-conditioned room.
- Equipment for mining cryptocurrencies. This can be a desktop computer, but it is still better to use special computing machines designed for this purpose.
- Quality cooling. Good ventilation will also be required to remove hot air from the room. Mining forces the «machines» to work at 100% load, which causes increased heat output. Therefore it is important to keep the room cool.

This market is constantly developing, and almost every day new discoveries are made in the field of cryptocurrency mining. Therefore, keeping track of technological changes and new methods of optimizing coin-mining results is a necessary condition for success.

Cryptocurrency mining is profitable as long as the value of the mined coins exceeds the costs of equipment and electricity. The difficulty indicator is of great importance for the cryptocurrency mining process, since it determines how much equipment and of what power must be used in the process. In fact, difficulty helps miners determine the most energy-efficient devices that provide the best profitability. The rate of issuance of new coins is also controlled through mining difficulty.