Proof of work (PoW) is a form of cryptographic proof in which one party proves to others that a certain amount of a specific computational effort has been expended. Verifiers can subsequently confirm this expenditure with minimal effort on their part. The concept was first implemented in Hashcash by Moni Naor and Cynthia Dwork in 1993 as a way to deter denial-of-service attacks and other service abuses such as spam on a network by requiring some work from a service requester, usually meaning processing time by a computer. The term "proof of work" was first coined and formalized in a 1999 paper by Markus Jakobsson and Ari Juels. The concept was adapted to digital tokens by Hal Finney in 2004 through the idea of "reusable proof of work" using the 160-bit secure hash algorithm 1 (SHA-1).
A cryptocurrency, crypto-currency, or crypto is a digital currency designed to work through a computer network that is not reliant on any central authority, such as a government or bank, to uphold or maintain it.
Litecoin is a decentralized peer-to-peer cryptocurrency and open-source software project released under the MIT/X11 license. Inspired by Bitcoin, Litecoin was among the earliest altcoins, starting in October 2011. In technical details, the Litecoin main chain shares a slightly modified Bitcoin codebase. The practical effects of those codebase differences are lower transaction fees, faster transaction confirmations, and faster mining difficulty retargeting. Due to its underlying similarities to Bitcoin, Litecoin has historically been referred to as the "silver to Bitcoin's gold." In 2022, Litecoin added optional privacy features via soft fork through the MWEB upgrade.
The bitcoin protocol is the set of rules that govern the functioning of bitcoin. Its key components and principles are: a peer-to-peer decentralized network with no central oversight; the blockchain technology, a public ledger that records all bitcoin transactions; mining and proof of work, the process to create new bitcoins and verify transactions; and cryptographic security.
Zerocoin is a privacy protocol proposed in 2013 by Johns Hopkins University professor Matthew D. Green and his graduate students, Ian Miers and Christina Garman. It was designed as an extension to the Bitcoin protocol that would improve Bitcoin transactions' anonymity by having coin-mixing capabilities natively built into the protocol. Zerocoin is not currently compatible with Bitcoin.
Ethereum is a decentralized blockchain with smart contract functionality. Ether is the native cryptocurrency of the platform. Among cryptocurrencies, ether is second only to bitcoin in market capitalization. It is open-source software.
NXT is an open source cryptocurrency and payment network launched in 2013 by anonymous software developer BCNext. It uses proof-of-stake to reach consensus for transactions—as such, there is a static money supply. Unlike Bitcoin, there is no mining. NXT was specifically conceived as a flexible platform around build applications and financial services, and serves as basis for ARDR (Ardor), a blockchain-as-a-service multichain platform developed by Jelurida, and IoTeX (cryptocurrency) the current steward of NXT as of 2021. NXT has been covered extensively in the "Call for Evidence" report by ESMA.
CryptoNote is an application layer protocol designed for use with cryptocurrencies that aims to solve specific problems identified in Bitcoin.
Monero is a cryptocurrency which uses a blockchain with privacy-enhancing technologies to obfuscate transactions to achieve anonymity and fungibility. Observers cannot decipher addresses trading Monero, transaction amounts, address balances, or transaction histories.
A decentralised application is an application that can operate autonomously, typically through the use of smart contracts, that run on a decentralized computing, blockchain or other distributed ledger system. Like traditional applications, DApps provide some function or utility to its users. However, unlike traditional applications, DApps operate without human intervention and are not owned by any one entity, rather DApps distribute tokens that represent ownership. These tokens are distributed according to a programmed algorithm to the users of the system, diluting ownership and control of the DApp. Without any one entity controlling the system, the application is therefore decentralised.
Ethereum Classic is a blockchain-based distributed computing platform that offers smart contract (scripting) functionality. It is open source and supports a modified version of Nakamoto consensus via transaction-based state transitions executed on a public Ethereum Virtual Machine (EVM).
Firo, formerly known as Zcoin, is a cryptocurrency aimed at using cryptography to provide better privacy for its users compared to other cryptocurrencies such as Bitcoin.
The Lightning Network (LN) is a payment protocol built on the bitcoin blockchain. It is intended to enable fast transactions among participating nodes and has been proposed as a solution to the bitcoin scalability problem.
The Bitcoin scalability problem refers to the limited capability of the Bitcoin network to handle large amounts of transaction data on its platform in a short span of time. It is related to the fact that records in the Bitcoin blockchain are limited in size and frequency.
EOS.IO is a blockchain protocol based on the cryptocurrency EOS. The smart contract platform claims to eliminate transaction fees and also conduct millions of transactions per second. It was developed by the private company Block.one and launched in 2017. The platform was later released as open-source software.
A blockchain is a shared database that records transactions between two parties in an immutable ledger. Blockchain documents and confirms pseudonymous ownership of all transactions in a verifiable and sustainable way. After a transaction is validated and cryptographically verified by other participants or nodes in the network, it is made into a "block" on the blockchain. A block contains information about the time the transaction occurred, previous transactions, and details about the transaction. Once recorded as a block, transactions are ordered chronologically and cannot be altered. This technology rose to popularity after the creation of Bitcoin, the first application of blockchain technology, which has since catalyzed other cryptocurrencies and applications.
Tron is a decentralized, proof-of-stake blockchain with smart contract functionality. The cryptocurrency native to the blockchain is known as Tronix (TRX). It was founded in March 2014 by Justin Sun and since 2017 has been overseen and supervised by the TRON Foundation, a non-profit organization in Singapore, established in the same year. It is open-source software.
Decentralized finance provides financial instruments and services through smart contracts on a programmable, permissionless blockchain. This approach reduces the need for intermediaries such as brokerages, exchanges, or banks. DeFi platforms enable users to lend or borrow funds, speculate on asset price movements using derivatives, trade cryptocurrencies, insure against risks, and earn interest in savings-like accounts. The DeFi ecosystem is built on a layered architecture and highly composable building blocks. While some applications offer high interest rates, they carry high risks. Coding errors and hacks are a common challenge in DeFi.
Stacks, formerly Blockstack, is a layer-2 blockchain that extends the use of Bitcoin to include smart contracts, decentralized finance ("DeFi"), non-fungible tokens (NFTs), and decentralized apps ("DApps"), while still maintaining Bitcoin finality. Stacks, like the Lightning Network, Merlin Chain, Rootstock Infrastructure Framework (RIF) and Dovi, is aimed at improving the functionality of Bitcoin.
The Aave Protocol is an open-source, decentralized finance (DeFi) protocol built on the Ethereum blockchain and released in 2020. It is one of the largest cryptocurrency liquidity protocols. The Aave Protocol uses smart contracts to automate processes, including distributing funds and handling collateral.
