How does cryptocurrency work?

While the cryptocurrencies themselves act as a medium for exchanging or for storing value, they all rely on a special type of public ledger technology called “blockchain” to record data and to keep track of all of the transactions being sent across the network.

A blockchain is exactly what it sounds like – a virtual chain of blocks each containing a batch of transactions and other data. Once each block is added to the chain, it becomes immutable, meaning the data stored inside it cannot be changed or removed.

Because cryptocurrencies are managed by a network of volunteer contributors known as “nodes” and not by a single intermediary, a system must be in place that ensures everyone participates honestly when recording and adding new data to the blockchain ledger.

The nodes perform a variety of roles on the network, from storing a full archive of all historical transactions to validating new transaction data. By having a distributed group of people all maintaining their own copy of the ledger, blockchain technology has the following advantages over traditional finance where a master copy is maintained by a single institution:

• There is no single point of failure: If one node fails it has zero impact on the blockchain ledger.
• There is no single source of truth that can be easily corrupted.

The nodes collectively manage the database and confirm new entries are valid transactions.

Think of it as having a cluster of computers take up the roles of a bank by consistently updating the balance sheets of users. In the case of distributed ledgers, however, the balance sheets aren’t stored in a single server. Instead, there are multiple copies of the balance sheets distributed across several computers, with each node, or computer connected to the network, functioning as a separate server. Therefore, even if one of the computers go offline, it wouldn’t be as detrimental as having a single server-based database go offline as can be the case in traditional banking systems.

This infrastructural design makes it possible for cryptocurrencies to evade the security mishaps that often plague fiat. It is difficult to attack or manipulate this system because the attackers must gain control of over 50% of computers connected to the blockchain network. Depending on how big the network is, it can be prohibitively expensive to carry out a coordinated attack. If you compare the amount required to attack established cryptocurrencies like bitcoin and what the attacker stands to gain at the end of the day, pursuing such an endeavor wouldn’t be viable financially.

Also, it is worth mentioning that the distributed nature of these digital assets establishes their censorship-resistant attributes. Unlike the case with banks, which governments regulate, cryptocurrencies have their databases spread across the globe. Therefore, when a government shuts down one of these computers or all the computers within its jurisdiction, the network will continue to function because there are potentially thousands of other nodes in other countries beyond the reach of one government.

So far in this guide, we have explained why cryptocurrencies are secure and why they are censorship-resistant. Now, let us take a look at how crypto transactions are vetted.