Blockchain: Cryptocurrency Terms Explained

The world of cryptocurrency can often seem complex and overwhelming to newcomers. At the heart of this digital financial revolution is a technology known as blockchain. This article aims to demystify the terminology associated with blockchain and cryptocurrency, providing a comprehensive glossary of key terms and concepts.

Understanding these terms is crucial for anyone looking to navigate the world of cryptocurrency effectively. Whether you’re a potential investor, a tech enthusiast, or just curious about the buzzwords you’ve heard in the news, this glossary will serve as a valuable resource.


Blockchain is the foundational technology that underpins cryptocurrencies. It is a type of distributed ledger that records transactions across many computers so that the record cannot be altered retroactively without the alteration of all subsequent blocks and the consensus of the network. This makes blockchain technology secure and robust against fraudulent activities.

The term ‘blockchain’ comes from the way the technology works. Each ‘block’ contains a list of transactions, and these blocks are linked together in a ‘chain’. This chain of blocks is constantly growing as new transactions are verified and added to the end of the chain.


A block, in the context of blockchain, refers to a collection of transaction data or information that is added to the blockchain. Each block contains a record of several transactions, a reference to the block that came immediately before it, and an answer to a complex mathematical problem. The process of creating a new block is known as ‘mining’.

Once a block is added to the blockchain, the information it contains is considered to be ‘confirmed’, and it cannot be changed or removed. This immutability is one of the key features of blockchain technology, and it’s one of the reasons why it’s considered to be a secure and reliable way of recording transactions.


The ‘chain’ in blockchain refers to the sequence of blocks that have been added to the blockchain over time. Each block in the chain contains a reference to the block that came before it, creating a linked list of blocks. This chain of blocks forms a complete and verifiable record of every transaction that has ever taken place on the blockchain.

Because each block contains a reference to the block that came before it, it’s impossible to alter a block without also altering every block that comes after it. This makes the blockchain extremely resistant to tampering and fraud.


Cryptocurrency is a type of digital or virtual currency that uses cryptography for security. Cryptocurrencies operate independently of a central bank, making them immune to government interference or manipulation. The most well-known cryptocurrency is Bitcoin, but there are thousands of other ‘altcoins’ available as well.

Cryptocurrencies are typically built on blockchain technology, which provides a decentralized and transparent way of recording and verifying transactions. This decentralization is one of the key attractions of cryptocurrencies, as it means that no single entity has control over the entire network.


Bitcoin is the first and most well-known cryptocurrency. It was created in 2009 by an unknown person or group of people using the pseudonym Satoshi Nakamoto. Bitcoin introduced the concept of blockchain technology and set the stage for the explosion of other cryptocurrencies that followed.

Bitcoin transactions are verified by network nodes through cryptography and recorded in a public distributed ledger called a blockchain. Bitcoin can be exchanged for other currencies, products, and services, and it’s often used as a store of value, similar to gold.


Altcoins are any cryptocurrencies that are not Bitcoin. The term ‘altcoin’ is a portmanteau of ‘alternative’ and ‘coin’, reflecting the fact that these cryptocurrencies were developed as alternatives to Bitcoin. There are thousands of altcoins available, each with its own unique features and uses.

Some of the most well-known altcoins include Ethereum, Ripple, and Litecoin. These altcoins often aim to improve upon the limitations of Bitcoin, offering faster transaction times, enhanced privacy features, or other benefits. However, Bitcoin remains the most widely used and valuable cryptocurrency by market capitalization.


Cryptography is a method of protecting information by transforming it into an unreadable format. Only those who possess a special key can decrypt the information, making it readable again. Cryptography is used in cryptocurrency to secure transactions and control the creation of new coins.

The cryptographic techniques used in cryptocurrency are extremely complex, but they’re also extremely secure. This security is one of the main reasons why cryptocurrencies have gained popularity as a method of online payment.

Public and Private Keys

In the context of cryptocurrency, a public key is a large numerical value that is used to encrypt data. The corresponding private key is used to decrypt the data. Together, these keys are known as a ‘key pair’.

When you create a cryptocurrency wallet, a key pair is generated. Your public key is used to create your wallet address, and your private key is used to sign transactions. It’s crucial to keep your private key secret, as anyone who has access to it can access and spend your cryptocurrency.


Hashing is a cryptographic process that takes an input (or ‘message’) and returns a fixed-size string of bytes. The output, known as the hash value, is unique to the input: even a small change to the input will produce a completely different output.

In the context of blockchain, hashing is used to create a unique identifier for each block. This identifier, known as the block’s ‘hash’, is included in the block’s data. If the block’s data is altered in any way, the hash will change, indicating that the block has been tampered with.

Wallets and Exchanges

A cryptocurrency wallet is a digital wallet used to store, send, and receive digital currency like Bitcoin. Most coins have an official wallet or a few officially recommended third-party wallets. To use any cryptocurrency, you will need to use a cryptocurrency wallet.

An exchange is a platform that allows users to buy, sell, or trade cryptocurrencies. Some exchanges allow users to trade for traditional fiat currencies, like the U.S. dollar, while others only allow for trading between cryptocurrencies. Each exchange has its own rules, accepted currencies, and fees.

Hot and Cold Wallets

Hot wallets are digital wallets that are connected to the internet. They are convenient for quick transactions, but they are also susceptible to hacking. Examples of hot wallets include online wallets, mobile wallets, and desktop wallets.

Cold wallets, on the other hand, are not connected to the internet. They are considered to be the most secure way to store cryptocurrencies. Examples of cold wallets include hardware wallets and paper wallets.

Centralized and Decentralized Exchanges

Centralized exchanges are platforms that are operated by a single entity or company. They function much like a traditional bank, in that they hold users’ funds and facilitate transactions between users. While centralized exchanges are user-friendly and often have high liquidity, they are also vulnerable to hacking.

Decentralized exchanges, on the other hand, operate without a central authority. Instead, transactions are facilitated directly between users through an automated process. While decentralized exchanges offer greater privacy and control, they can be more difficult to use and often have lower liquidity.


Mining is the process of adding new transactions to the blockchain. In the context of cryptocurrencies, mining involves solving complex mathematical problems in order to add a new block to the blockchain. This process requires significant computational power and energy consumption.

When a miner successfully adds a new block to the blockchain, they are rewarded with a certain amount of cryptocurrency. This reward serves as an incentive for miners to continue mining and maintaining the blockchain.

Proof of Work

Proof of Work (PoW) is a consensus algorithm used in blockchain networks. It requires miners to solve a complex mathematical problem in order to add a new block to the blockchain. The difficulty of these problems ensures that blocks are added to the blockchain at a consistent rate.

The PoW system is designed to deter cyber-attacks such as distributed denial of service (DDoS) attacks by requiring some work from the service requester, usually in the form of processing time.

Proof of Stake

Proof of Stake (PoS) is another type of consensus algorithm used in blockchain networks. Unlike PoW, PoS does not require miners to solve complex mathematical problems. Instead, the creator of a new block is chosen in a deterministic way, depending on its wealth, also defined as stake.

The PoS method is generally considered to be more energy-efficient than the PoW method, as it does not require miners to use large amounts of computational power. However, it can also lead to a greater concentration of wealth and power within the network.

Smart Contracts

Smart contracts are self-executing contracts with the terms of the agreement directly written into lines of code. The code and the agreements contained therein exist across a distributed, decentralized blockchain network.

Smart contracts allow trusted transactions and agreements to be carried out among disparate, anonymous parties without the need for a central authority, legal system, or external enforcement mechanism. They render transactions traceable, transparent, and irreversible.


Ethereum is an open-source, blockchain-based platform that enables developers to build and deploy decentralized applications (dApps). It was proposed in late 2013 by Vitalik Buterin, a cryptocurrency researcher and programmer.

Ethereum’s native cryptocurrency, Ether (ETH), is used to facilitate transactions within the network. However, Ethereum is perhaps best known for its support of smart contracts, which have opened up a wide range of possibilities for blockchain technology.


Decentralized applications, or dApps, are applications that run on a P2P network of computers rather than a single computer. They have been popularized by distributed ledger technologies (DLT) such as the Ethereum blockchain, where dApps are often referred to as smart contracts.

dApps have their backend code running on a decentralized peer-to-peer network, as opposed to typical applications where the backend code is running on centralized servers. A dApp can have frontend code and user interfaces written in any language that can make calls to its backend. Furthermore, its frontend can be hosted on decentralized storage such as Swarm or IPFS.


Blockchain and cryptocurrency are complex fields with a lot of specialized terminology. However, with a bit of study and patience, it’s possible to gain a solid understanding of these concepts. This glossary should serve as a useful reference as you navigate the world of cryptocurrency.

Remember, while the technology behind cryptocurrencies is incredibly secure, the world of cryptocurrency can be risky. Always do your own research and consider your financial situation carefully before investing in cryptocurrency.