A blockchain is essentially a chain of blocks. Blocks contain digital information, think of them as packets of data connected like Christmas presents. In the case of the bitcoin blockchain: Within each block is a series of bitcoin transactions that occur over a period of time.


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In order to obey the rules for building a chain, a change in the hash sum has to be written off to the next block, causing a change in its own hash sum. In this case, the previous blocks are not affected.

Blockchain technology is a system used to build cryptocurrencies, which is a distributed database (ledger). Information about the various transactions is recorded in the chain and the blockchain works without communicating with the central server. The main function of the blockchain is to store blocks (elements) containing temporal data and a link to the previous network node. Blockchain technology is constantly evolving, improving, revealing its potential and is increasingly used in various fields.


A feature of a distributed network is the total transparency and availability of information for each of the participants. The chain is subject to constant data control, so that manipulation or modification of the part of the chain that has already been formed is impossible. New information appearing on the blockchain is completely transparent and available for download by any user. With Bitcoin, when installing an official “heavy” wallet, a person downloads transaction information to a PC for the life of the cryptocurrency. To get information about a specific operation, you need to use special services. Just enter the block number, operation or wallet address in the search box to get detailed information.

Technology in simple terms

A blockchain network is an interconnected chain of blocks that works according to certain rules. The account book is located on the PC kit, after each operation it is updated. A variety of data is entered into the cells of the system, starting with information about the transaction and ending with the ownership of any work by a particular author.
Blockchain is a chain of blocks connected to each other, filled with certain information (new records and information about the previous node).

Data encryption

Automatic encryption of information ensures network privacy. A cryptographic rule is used that excludes the wallet number from being associated with a specific user. The information contained in the channel elements is not shared with third parties. High speed and accuracy of operations. Blockchain technology guarantees instant transactions without intermediaries. Banking institutions, payment networks and notary offices are simply not necessary. The correctness of operation is checked by each user of the network with maximum accuracy.

Blockchain elements are filled with information about transactions in the network (user actions: transfers, purchases, registration of rights, etc.). Once the operation is created, the transaction is sent to the mempool and waits for confirmation. As soon as the block is formed, the participants check it: if valid, they add it to the general chain. Accounts are constantly updated and always up to date (see Bitcoin Fortress for example).

Availability of copies on each user's computer. The blockchain resides on tens of millions of computers at the same time, so there is no need to coordinate every transaction. Whenever a new operation appears, it is verified by the network participants. Nobody has the right to change the order of the blocks or make changes to the content. The key to a particular block of information resides with a particular user who has access to the information.


Governments of many countries are irritated by the advantages of blockchain technology: independence and the inability to control the operation of the system. There is no central server to store information, and the information resides on the computers of millions of users. Getting even some of the control will require a lot of money and a lot of power. Blockchain technology has a completely new structure and is ahead of existing systems in terms of reliability. Currently, information about individuals, transactions, bank accounts, and other data is stored on one or more servers. If it is corrupted or the information is stolen, the system will crash. In the case of blockchain technology, this is impossible: the chain is not afraid of hackers and external influences.