Blockchain Oracle
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Blockchain Oracle
A blockchain oracle is a third-party service that connects smart contracts with the outside world, primarily to feed information in from the world, but also the reverse. Information from the world encapsulates multiple sources, so that decentralized knowledge is obtained. Oracles provide a way for the decentralized Web3 ecosystem to access existing data sources, legacy systems, and advanced computations. Decentralized oracle networks (DONs) enable the creation of hybrid smart contracts, where on-chain code and off-chain infrastructure are combined to support advanced decentralized applications (dApps) that react to real-world events and interoperate with traditional systems. Examples Many Ethereum applications use oracles. For example, prediction market Augur An augur was a priest and official in the classical Roman world. His main role was the practice of augury, the interpretation of the will of the gods by studying the flight of birds. Determinations were based ...
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Blockchain
A blockchain is a type of distributed ledger technology (DLT) that consists of growing lists of records, called ''blocks'', that are securely linked together using cryptography. Each block contains a cryptographic hash of the previous block, a timestamp, and transaction data (generally represented as a Merkle tree, where data nodes are represented by leaves). The timestamp proves that the transaction data existed when the block was created. Since each block contains information about the previous block, they effectively form a ''chain'' (compare linked list data structure), with each additional block linking to the ones before it. Consequently, blockchain transactions are irreversible in that, once they are recorded, the data in any given block cannot be altered retroactively without altering all subsequent blocks. Blockchains are typically managed by a peer-to-peer, peer-to-peer (P2P) computer network for use as a public distributed ledger, where nodes collectively adhere to ...
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Smart Contracts
A smart contract is a computer program or a transaction protocol that is intended to automatically execute, control or document events and actions according to the terms of a contract or an agreement. The objectives of smart contracts are the reduction of need for trusted intermediators, arbitration costs, and fraud losses, as well as the reduction of malicious and accidental exceptions. Smart contracts are commonly associated with cryptocurrencies, and the smart contracts introduced by Ethereum are generally considered a fundamental building block for decentralized finance (DeFi) and NFT applications. Vending machines are mentioned as the oldest piece of technology equivalent to smart contract implementation. The original Ethereum white paper by Vitalik Buterin in 2014 describes the Bitcoin protocol as a weak version of the smart contract concept as originally defined by Nick Szabo, and proposed a stronger version based on the Solidity language, which is Turing complete. Si ...
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Decentralization
Decentralization or decentralisation is the process by which the activities of an organization, particularly those regarding planning and decision making, are distributed or delegated away from a central, authoritative location or group. Concepts of decentralization have been applied to group dynamics and management science in private businesses and organizations, political science, law and public administration, economics, money and technology. History The word "''centralisation''" came into use in France in 1794 as the post-French Revolution, Revolution French Directory leadership created a new government structure. The word "''décentralisation''" came into usage in the 1820s. "Centralization" entered written English in the first third of the 1800s; mentions of decentralization also first appear during those years. In the mid-1800s Alexis de Tocqueville, Tocqueville would write that the French Revolution began with "a push towards decentralization...[but became,] in the e ...
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Web3
Web3 (also known as Web 3.0) is an idea for a new iteration of the World Wide Web which incorporates concepts such as decentralization, blockchain technologies, and token-based economics. Some technologists and journalists have contrasted it with Web 2.0, wherein they say data and content are centralized in a small group of companies sometimes referred to as " Big Tech". The term "Web3" was coined in 2014 by Ethereum co-founder Gavin Wood, and the idea gained interest in 2021 from cryptocurrency enthusiasts, large technology companies, and venture capital firms. Commentators associated with the Open Rights Group argue that Web3 will provide increased data security, scalability, and privacy for users and combat the influence of large technology companies. They also raise concerns about the decentralized web component of Web3, citing the potential for low moderation and the proliferation of harmful content. Some have expressed concerns over the centralization of wealth to a sma ...
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Smart Contract
A smart contract is a computer program or a transaction protocol that is intended to automatically execute, control or document events and actions according to the terms of a contract or an agreement. The objectives of smart contracts are the reduction of need for trusted intermediators, arbitration costs, and fraud losses, as well as the reduction of malicious and accidental exceptions. Smart contracts are commonly associated with cryptocurrencies, and the smart contracts introduced by Ethereum are generally considered a fundamental building block for decentralized finance (DeFi) and NFT applications. Vending machines are mentioned as the oldest piece of technology equivalent to smart contract implementation. The original Ethereum white paper by Vitalik Buterin in 2014 describes the Bitcoin protocol as a weak version of the smart contract concept as originally defined by Nick Szabo, and proposed a stronger version based on the Solidity language, which is Turing complete. Si ...
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Decentralized Application
A decentralised application (DApp, dApp, Dapp, or dapp) 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. Decentralised applications have been popularised by distributed ledger technologies (DLT), such as the Ethereum blockchain, Blockmec, on which DApps are built, amongst other public blockchains. The trustless and transparent nature of DApps have led to greater d ...
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Ethereum
Ethereum is a decentralized, open-source blockchain with smart contract functionality. Ether (Abbreviation: ETH; sign: Ξ) is the native cryptocurrency of the platform. Among cryptocurrencies, ether is second only to bitcoin in market capitalization. Ethereum was conceived in 2013 by programmer Vitalik Buterin. Additional founders of Ethereum included Gavin Wood, Charles Hoskinson, Anthony Di Iorio and Joseph Lubin. In 2014, development work began and was crowdfunded, and the network went live on 30 July 2015. Ethereum allows anyone to deploy permanent and immutable decentralized applications onto it, with which users can interact. Decentralized finance (DeFi) applications provide a broad array of financial services without the need for typical financial intermediaries like brokerages, exchanges, or banks, such as allowing cryptocurrency users to borrow against their holdings or lend them out for interest. Ethereum also allows users to create and exchange NFTs, which are un ...
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Prediction Market
Prediction markets (also known as betting markets, information markets, decision markets, idea futures or event derivatives) are open markets where specific outcomes can be predicted using financial incentives. Essentially, they are exchange-traded markets created for the purpose of trading the outcome of events. The market prices can indicate what the crowd thinks the probability of the event is. A prediction market contract trades between 0 and 100%. The most common form of a prediction market is a binary option market, which will expire at the price of 0 or 100%. Prediction markets can be thought of as belonging to the more general concept of crowdsourcing which is specially designed to aggregate information on particular topics of interest. The main purposes of prediction markets are eliciting aggregating beliefs over an unknown future outcome. Traders with different beliefs trade on contracts whose payoffs are related to the unknown future outcome and the market prices of the ...
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Augur (software)
Augur is a decentralized prediction market platform built on the Ethereum blockchain. Augur is developed by Forecast Foundation, which was founded in 2014 by Jack Peterson, Joey Krug, and Jeremy Gardner. Forecast Foundation is advised by Ron Bernstein, founder of now-defunct company Intrade, and Ethereum founder Vitalik Buterin. Operation Augur allows any user to create a prediction market on any topic. There are two kinds of markets: *Categorical markets have up to seven options; for example, "Will Alice win X election?" with "yes" and "no" as options, or "Who will win X election?" with five candidates as options. These markets are winners take all, making them similar to binary options. *Scalar markets offer a spectrum of numerical outcomes; for example, "What will the closing price of Apple's stock be on January 1 2021?" Traders can "long" or "short" any value, i.e. bet that the result will be higher or lower than a certain value. If a trader longs at X value, the more a ...
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Cryptography
Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or ''-logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. Core concepts related to information security ( data confidentiality, data integrity, authentication, and non-repudiation) are also central to cryptography. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications. Cryptography prior to the modern age was effectively synonymo ...
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Smart Lock
A smart lock is an electromechanical lock that is designed to perform locking and unlocking operations on a door when it receives a prompt via an electronic keypad, biometric sensor, access card, Bluetooth, or Wi-FI from a registered mobile device. These locks are called smart locks because they use advanced technology and Internet communication to enable easier access for users and enhanced security from intruders. The main components of a smart lock include the physical lock, the key (which can be electronic, digitally encrypted, or a virtual key to provide keyless entry), a secure Bluetooth or Wi-Fi connection, and a management mobile app. Smart locks may also monitor access and send alerts in response to the different events it monitors as well as other critical events related to the status of the device. Smart locks can be considered part of a smart home. Most smart locks are installed on mechanical locks (simple types of locks, including deadbolts) and they physically upgrad ...
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Man-in-the-middle Attack
In cryptography and computer security, a man-in-the-middle, monster-in-the-middle, machine-in-the-middle, monkey-in-the-middle, meddler-in-the-middle, manipulator-in-the-middle (MITM), person-in-the-middle (PITM) or adversary-in-the-middle (AiTM) attack is a cyberattack where the attacker secretly relays and possibly alters the communications between two parties who believe that they are directly communicating with each other, as the attacker has inserted themselves between the two parties. One example of a MITM attack is active eavesdropping, in which the attacker makes independent connections with the victims and relays messages between them to make them believe they are talking directly to each other over a private connection, when in fact the entire conversation is controlled by the attacker. The attacker must be able to intercept all relevant messages passing between the two victims and inject new ones. This is straightforward in many circumstances; for example, an attacker wit ...
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