A digital wallet, also known as an e-wallet or mobile wallet, is an electronic device, online service, or software program that allows one party to make electronic transactions with another party bartering digital currency units for goods and services. This can include purchasing items either online or at the point of sale in a brick and mortar store, using either mobile payment or using a laptop or other personal computer. Money can be deposited in the digital wallet prior to any transactions or, in other cases, an individual's bank account can be linked to the digital wallet. Users might also have their driver's license, health card, loyalty card(s) and other ID documents stored within the wallet. The credentials can be passed to a merchant's terminal wirelessly via near field communication (NFC).
Bitcoin is the first decentralized cryptocurrency. Based on a free-market ideology, bitcoin was invented in 2008 by Satoshi Nakamoto, an unknown entity. Use of bitcoin as a currency began in 2009, with the release of its open-source implementation. In 2021, El Salvador adopted it as legal tender. It is mostly seen as an investment and has been described by some scholars as an economic bubble. As bitcoin is pseudonymous, its use by criminals has attracted the attention of regulators, leading to its ban by several countries as of 2021.
A cryptocurrency, crypto-currency, or colloquially, 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.
Coinbase Global, Inc., branded Coinbase, is an American publicly traded company that operates a cryptocurrency exchange platform. Coinbase is a distributed company; all employees operate via remote work. It is the largest cryptocurrency exchange in the United States in terms of trading volume. The company was founded in 2012 by Brian Armstrong and Fred Ehrsam. In May 2020, Coinbase announced it would shut its San Francisco, California, headquarters and change operations to remote-first, part of a wave of several major tech companies closing headquarters in San Francisco in the wake of the COVID-19 pandemic.
Charles Shrem IV is an American entrepreneur and bitcoin advocate. He co-founded the now-defunct startup company BitInstant, and is a founding member of the Bitcoin Foundation. In 2014 he was sentenced to two years in prison for aiding and abetting the operation of an unlicensed money-transmitting business related to the Silk Road marketplace. He was released from prison in 2016. In 2017, he joined Jaxx and served as its chief operating officer, and founded cryptocurrency advisory CryptoIQ.
Blockchain.com is a cryptocurrency financial services company. The company began as the first Bitcoin blockchain explorer in 2011 and later created a cryptocurrency wallet that accounted for 28% of bitcoin transactions between 2012 and 2020. It also operates a cryptocurrency exchange and provides institutional markets lending business and data, charts, and analytics.
Vertcoin is an open-source cryptocurrency created in early 2014, that focuses on decentralization. Vertcoin uses a proof-of-work mechanism to issue new coins and incentivize miners to secure the network and validate transactions. Vertcoin is designed to be mined via graphics cards instead of through ASICs.
Bitcoin Core is free and open-source software that serves as a bitcoin node and provides a bitcoin wallet which fully verifies payments. It is considered to be bitcoin's reference implementation. Initially, the software was published by Satoshi Nakamoto under the name "Bitcoin", and later renamed to "Bitcoin Core" to distinguish it from the network. It is also known as the Satoshi client. Bitcoin Core includes a transaction verification engine and connects to the bitcoin network as a full node.
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.
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).
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.
A cryptocurrency wallet is a device, physical medium, program or an online service which stores the public and/or private keys for cryptocurrency transactions. In addition to this basic function of storing the keys, a cryptocurrency wallet more often offers the functionality of encrypting and/or signing information. Signing can for example result in executing a smart contract, a cryptocurrency transaction, identification, or legally signing a 'document'.
Bitcoin Gold (BTG) is a cryptocurrency which was created as a hard fork of bitcoin.
Cryptocurrency and crime describe notable examples of cybercrime related to theft of cryptocurrencies and some methods or security vulnerabilities commonly exploited. Cryptojacking is a form of cybercrime specific to cryptocurrencies used on websites to hijack a victim's resources and use them for hashing and mining cryptocurrency.
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.
MetaMask is a software cryptocurrency wallet used to interact with the Ethereum blockchain. It allows a user to access their Ethereum wallet through a browser extension or mobile app, which can then be used to interact with decentralized applications. MetaMask is developed by Consensys, a blockchain software company focusing on Ethereum-based tools and infrastructure.
Uniswap is a decentralized cryptocurrency exchange that uses a set of smart contracts to create liquidity pools for the execution of trades. It is an open source project and falls into the category of a DeFi product because it uses smart contracts to facilitate trades instead of a centralized exchange. The protocol facilitates automated transactions between cryptocurrency tokens on the Ethereum blockchain through the use of smart contracts. As of December 2024, Uniswap is estimated to be the second largest decentralized exchange and the seven-largest cryptocurrency exchange overall by daily trading volume.
Solana is a blockchain platform which uses a proof-of-stake mechanism to provide smart contract functionality. Its native cryptocurrency is SOL.
Colored Coins is an open-source protocol that allows users to represent and manipulate immutable digital resources on top of Bitcoin transactions. They are a class of methods for representing and maintaining real-world assets on the Bitcoin blockchain, which may be used to establish asset ownership. Colored coins are bitcoins with a mark on them that specifies what they may be used for. Colored coins have also been considered a precursor to NFTs.
