Update terminology.md

terminology.md

@@ -163,3 +163,341 @@ ZCash
 * **DApp**. Decentralized App, what applications using smart contracts are called in the Ethereum community. The goal of a DApp is (well, should be) to have a nice UI to your smart contracts plus any extra niceties like IPFS (a neat way to store and serve stuff in a decentralized network, not made by Ethereum but a kindred spirit). While DApps can be run from a central server if that server can talk to an Ethereum node, they can also be run locally on top of any Ethereum node peer. [Take a minute: unlike normal webapps, DApps may not be served from a server. They may use the blockchain to submit transactions and retrieve data (important data!) rather than a central database. Instead of a typical user login system, users may be represented by a wallet addresses and keep any user data local. Many things can be architected differently from the current web.]
 
 
+
+## BLockchaing - More to merge
+
+Address
+Addresses (Cryptocurrency addresses) are used to receive and send transactions on the network. An address is a string of alphanumeric characters, but can also be represented as a scannable QR code.
+
+Agreement Ledger
+An agreement ledger is distributed ledger used by two or more parties to negotiate and reach agreement. 
+
+Attestation Ledger
+A distributed ledger providing a durable record of agreements, commitments or statements, providing evidence (attestation) that these agreements, commitments or statements were made. 
+
+ASIC
+ASIC is an acronym for "Application Specific Integrated Circuit". ASICs are silicon chips specifically designed to do a single task. In the case of bitcoin, they are designed to process SHA-256 hashing problems to mine new bitcoins.
+
+Bitcoin (uppercase)
+The well known cryptocurrency, based on the proof-of-work blockchain.
+
+bitcoin (lowercase)
+The specific collection of technologies used by Bitcoin’s ledger, a particular solution. Note that the currency is itself one of these technologies, as it provides the miners with the incentive to mine. 
+
+Blockchain
+A blockchain is a type of distributed ledger, comprised of unchangable, digitally recorded data in packages called blocks (rather like collating them on to a single sheet of paper). Each block is then ‘chained’ to the next block, using a cryptographic signature. This allows block chains to be used like a ledger, which can be shared and accessed by anyone with the appropriate permissions.
+
+Block Height
+Block height refers to the number of blocks connected together in the block chain. For example, Height 0, would be the very first block, which is also called the Genesis Block.
+
+Block Reward
+The reward given to a miner which has successfully hashed a transaction block. Block rewards can be a mixture of coins and transaction fees, depending on the policy used by the cryptocurrency in question, and whether all of the coins have already been successfully mined. The current block reward for the Bitcoin network is 25 bitcoins for each block.
+
+Central Ledger
+A central ledger refers to a ledger maintained by a central agency. 
+
+Confirmation
+A confirmation means that the blockchain transaction has been verified by the network. This happens through a process known as mining, in a proof-of-work system (e.g. Bitcoin). Once a transaction is confirmed, it cannot be reversed or double spent. The more confirmations a transaction has, the harder it becomes to perform a double spend attack.
+
+Consensus Process
+The process a group of peers responsible for maintaining a distributed ledger use to reach consensus on the ledger’s contents. 
+
+Consensus Point
+A point – either in time, or defined in terms of a set number or volume of records to be added to the ledger – where peers meet to agree the state of the ledger.
+
+Cryptocurrency
+A form of digital currency based on mathematics, where encryption techniques are used to regulate the generation of units of currency and verify the transfer of funds. Furthermore, cryptocurrencies operate independently of a central bank.
+
+Digital Commodity
+A digital commodity is a scarce, electronically transferrable, intangible, with a market value.
+
+Digital Identity
+A digital identity is an online or networked identity adopted or claimed in cyberspace by an individual, organization, or electronic device.
+
+Distributed Ledger
+Distributed ledgers are a type of database that are spread across multiple sites, countries or institutions. Records are stored one after the other in a continuous ledger. Distributed ledger data can be either "permissioned" or "unpermissioned" to control who can view it. 
+
+Difficulty
+Difficulty, in Proof-of-Work mining, is how hard it is to verify blocks in a blockchain network. In the Bitcoin network, the difficulty of mining adjusts verifying blocks every 2016 blocks. This is to keep block verification time at ten minutes.
+
+Double Spend
+Double spend refers to a scenario, in the Bitcoin network, where someone tries to send a bitcoin transaction to two different recipients at the same time. However, once a bitcoin transaction is confirmed, it makes it nearly impossible to double spend it. The more confirmations that a particular transaction has, the harder it becomes to double spend the bitcoins.
+
+Genesis Block
+The very first block in a block chain.
+
+Halving
+Bitcoins have a finite supply, which makes them a scarce digital commodity. The total amount of bitcoins that will ever be issued is 21 million. The number of bitcoins generated per block is decreased 50% every four years. This is called “halving.” The final halving will take place in the year 2140.
+
+Hashrate
+The number of hashes that can be performed by a bitcoin miner in a given period of time (usually a second).
+
+Initial Coin Offering (ICO)
+An Initial Coin Offering (also called an ICO) is an event in which a new cryptocurrency sells advance tokens from its overall coinbase, in exchange for upfront capital. ICOs are frequently used for developers of a new cryptocurrency to raise capital.
+
+Ledger
+An append-only record store, where records are immutable and may hold more general information than financial records. 
+
+Litecoin
+A peer-to-peer cryptocurrency based on the Scrypt proof-of-work network. Sometimes referred to as the silver of bitcoin's gold. 
+
+Mining
+The process by which transactions are verified and added to a blockchain. This process of solving cryptographic problems using computing hardware also triggers the release of cryptocurrencies. 
+
+Multi Signature
+Multi-signature (multisig) addresses allow multiple parties to require more than one key to authorize a transaction. The needed number of signatures is agreed at the creation of the address. Multi signature addresses have a much greater resistance to theft.
+
+Off-Ledger Currency
+A currency minted off-ledger and used on-ledger. An example of this would be using distributed ledgers to manage a national currency.
+
+On-Ledger Currency
+A currency minted on-ledger and used on-ledger. An example of this would be the cryptocurrency, Bitcoin.
+
+P2P
+Peer-to-peer (P2P) refers to the decentralized interactions that happen between at least two parties in a highly interconnected network. P2P participants deal directly with each other through a single mediation point.
+
+Participant
+An actor who can access the ledger: read records or add records to. 
+
+Peer
+An actor that shares responsibility for maintaining the identity and integrity of the ledger. 
+
+Permissioned Ledger
+A permissioned ledger is a ledger where actors must have permission to access the ledger. Permissioned ledgers may have one or many owners. When a new record is added, the ledger’s integrity is checked by a limited consensus process. This is carried out by trusted actors — government departments or banks, for example — which makes maintaining a shared record much simpler that the consensus process used by unpermissioned ledgers. Permissioned block chains provide highly-verifiable data sets because the consensus process creates a digital signature, which can be seen by all parties. A permissioned ledger is usually faster than an unpermissioned ledger.
+
+Private Currency
+A currency issued by a private individual or firm, typically secured against uninsured assets. 
+
+Private Key
+A private key is a string of data that shows you have access to bitcoins in a specific wallet. Private keys can be thought of as a password; private keys must never be revealed to anyone but you, as they allow you to spend the bitcoins from your bitcoin wallet through a cryptographic signature.
+
+Proof-of-Stake
+An alternative to the proof-of-work system, in which your existing stake in a cryptocurrency (the amount of that currency that you hold) is used to calculate the amount of that currency that you can mine.
+
+Proof-of-Work
+A system that ties mining capability to computational power. Blocks must be hashed, which is in itself an easy computational process, but an additional variable is added to the hashing process to make it more difficult. When a block is successfully hashed, the hashing must have taken some time and computational effort. Thus, a hashed block is considered proof of work.
+
+Ripple
+A payment network built on distributed ledgers that can be used to transfer any currency. The network consists of payment nodes and gateways operated by authorities. Payments are made using a series of IOUs, and the network is based on trust relationships.
+
+Replicated Ledger
+A ledger with one master (authoritative) copy of the data, and many slave (non-authoritative) copies.
+
+Scrypt
+An alternative proof of work system to SHA-256, designed to be particularly friendly to CPU and GPU miners, while offering little advantage to ASIC miners.
+
+SHA 256
+The cryptographic function used as the basis for bitcoin’s proof of work system.
+
+Smart Contracts
+Smart contracts are contracts whose terms are recorded in a computer language instead of legal language. Smart contracts can be automatically executed by a computing system, such as a suitable distributed ledger system.
+
+Tokenless Ledger
+A tokenless ledger refers to a distributed ledger that doesn’t require a native currency to operate.
+
+Transaction Block
+A collection of transactions on the bitcoin network, gathered into a block that can then be hashed and added to the blockchain.
+
+Transaction Fee
+A small fee imposed on some transactions sent across the bitcoin network. The transaction fee is awarded to the miner that successfully hashes the block containing the relevant transaction.
+
+Unpermissioned ledgers
+Unpermissioned ledgers such as Bitcoin have no single owner — indeed, they cannot be owned. The purpose of an unpermissioned ledger is to allow anyone to contribute data to the ledger and for everyone in possession of the ledger to have identical copies. This creates censorship resistance, which means that no actor can prevent a transaction from being added to the ledger. Participants maintain the integrity of the ledger by reaching a consensus about its state
+
+
+# Etherium
+Blockchain Glossary: From A-Z
+51% Attack
+
+When more than half of the computing power of a cryptocurrency network is controlled by a single entity or group, this entity or group may issue conflicting transactions to harm the network, should they have the malicious intent to do so.
+
+Address
+
+Cryptocurrency addresses are used to send or receive transactions on the network. An address usually presents itself as a string of alphanumeric characters.
+
+ASIC
+
+Short form for ‘Application Specific Integrated Circuit’. Often compared to GPUs, ASICs are specially made for mining and may offer significant power savings.
+
+Bitcoin
+
+Bitcoin is the first decentralised, open source cryptocurrency that runs on a global peer to peer network, without the need for middlemen and a centralised issuer.
+
+Block
+
+Blocks are packages of data that carry permanently recorded data on the blockchain network.
+
+Blockchain
+
+A blockchain is a shared ledger where transactions are permanently recorded by appending blocks. The blockchain serves as a historical record of all transactions that ever occurred, from the genesis block to the latest block, hence the name blockchain.
+
+Block Explorer
+
+Block explorer is an online tool to view all transactions, past and current, on the blockchain. They provide useful information such as network hash rate and transaction growth.
+
+Block Height
+
+The number of blocks connected on the blockchain.
+
+Block Reward
+
+A form of incentive for the miner who successfully calculated the hash in a block during mining. Verification of transactions on the blockchain generates new coins in the process, and the miner is rewarded a portion of those.
+
+Central Ledger
+
+A ledger maintained by a central agency.
+
+Confirmation
+
+The successful act of hashing a transaction and adding it to the blockchain.
+
+Consensus
+
+Consensus is achieved when all participants of the network agree on the validity of the transactions, ensuring that the ledgers are exact copies of each other.
+
+Cryptocurrency
+
+Also known as tokens, cryptocurrencies are representations of digital assets.
+
+Cryptographic Hash Function
+
+Cryptographic hashes produce a fixed-size and unique hash value from variable-size transaction input. The SHA-256 computational algorithm is an example of a cryptographic hash.
+
+Dapp
+
+A decentralised application (Dapp) is an application that is open source, operates autonomously, has its data stored on a blockchain, incentivised in the form of cryptographic tokens and operates on a protocol that shows proof of value.
+
+DAO
+
+Decentralised Autonomous Organizations can be thought of as corporations that run without any human intervention and surrender all forms of control to an incorruptible set of business rules.
+
+Distributed Ledger
+
+Distributed ledgers are ledgers in which data is stored across a network of decentralized nodes. A distributed ledger does not have to have its own currency and may be permissioned and private.
+
+Distributed Network
+
+A type of network where processing power and data are spread over the nodes rather than having a centralised data centre.
+
+Difficulty
+
+This refers to how easily a data block of transaction information can be mined successfully.
+
+Digital Signature
+
+A digital code generated by public key encryption that is attached to an electronically transmitted document to verify its contents and the sender’s identity.
+
+Double Spending
+
+Double spending occurs when a sum of money is spent more than once.
+
+Ethereum
+
+Ethereum is a blockchain-based decentralised platform for apps that run smart contracts, and is aimed at solving issues associated with censorship, fraud and third party interference.
+
+EVM
+
+The Ethereum Virtual Machine (EVM) is a Turing complete virtual machine that allows anyone to execute arbitrary EVM Byte Code. Every Ethereum node runs on the EVM to maintain consensus across the blockchain.
+
+Fork
+
+Forks create an alternate version of the blockchain, leaving two blockchains to run simultaneously on different parts of the network.
+
+Genesis Block
+
+The first or first few blocks of a blockchain.
+
+Hard Fork
+
+A type of fork that renders previously invalid transactions valid, and vice versa. This type of fork requires all nodes and users to upgrade to the latest version of the protocol software.
+
+Hash
+
+The act of performing a hash function on the output data. This is used for confirming coin transactions.
+
+Hash Rate
+
+Measurement of performance for the mining rig is expressed in hashes per second.
+
+Hybrid PoS/PoW
+
+A hybrid PoS/PoW allows for both Proof of Stake and Proof of Work as consensus distribution algorithms on the network. In this method, a balance between miners and voters (holders) may be achieved, creating a system of community-based governance by both insiders (holders) and outsiders (miners).
+
+Mining
+
+Mining is the act of validating blockchain transactions. The necessity of validation warrants an incentive for the miners, usually in the form of coins. In this cryptocurrency boom, mining can be a lucrative business when done properly. By choosing the most efficient and suitable hardware and mining target, mining can produce a stable form of passive income.
+
+Multi-Signature
+
+Multi-signature addresses provide an added layer of security by requiring more than one key to authorize a transaction.
+
+Node
+
+A copy of the ledger operated by a participant of the blockchain network.
+
+Oracles
+
+Oracles work as a bridge between the real world and the blockchain by providing data to the smart contracts.
+
+Peer to Peer
+
+Peer to Peer (P2P) refers to the decentralized interactions between two parties or more in a highly-interconnected network. Participants of a P2P network deal directly with each other through a single mediation point.
+
+Public Address
+
+A public address is the cryptographic hash of a public key. They act as email addresses that can be published anywhere, unlike private keys.
+
+Private Key
+
+A private key is a string of data that allows you to access the tokens in a specific wallet. They act as passwords that are kept hidden from anyone but the owner of the address.
+
+Proof of Stake
+
+A consensus distribution algorithm that rewards earnings based on the number of coins you own or hold. The more you invest in the coin, the more you gain by mining with this protocol.
+
+Proof of Work
+
+A consensus distribution algorithm that requires an active role in mining data blocks, often consuming resources, such as electricity. The more ‘work’ you do or the more computational power you provide, the more coins you are rewarded with.
+
+Scrypt
+
+Scrypt is a type of cryptographic algorithm and is used by Litecoin. Compared to SHA256, this is quicker as it does not use up as much processing time.
+
+SHA-256
+
+SHA-256 is a cryptographic algorithm used by cryptocurrencies such as Bitcoin. However, it uses a lot of computing power and processing time, forcing miners to form mining pools to capture gains.
+
+Smart Contracts
+
+Smart contracts encode business rules in a programmable language onto the blockchain and are enforced by the participants of the network.
+
+Soft Fork
+
+A soft fork differs from a hard fork in that only previously valid transactions are made invalid. Since old nodes recognize the new blocks as valid, a soft fork is essentially backward-compatible. This type of fork requires most miners upgrading in order to enforce, while a hard fork requires all nodes to agree on the new version.
+
+Solidity
+
+Solidity is Ethereum’s programming language for developing smart contracts.
+
+Testnet
+
+A test blockchain used by developers to prevent expending assets on the main chain.
+
+Transaction Block
+
+A collection of transactions gathered into a block that can then be hashed and added to the blockchain.
+
+Transaction Fee
+
+All cryptocurrency transactions involve a small transaction fee. These transaction fees add up to account for the block reward that a miner receives when he successfully processes a block.
+
+Turing Complete
+
+Turing complete refers to the ability of a machine to perform calculations that any other programmable computer is capable of. An example of this is the Ethereum Virtual Machine (EVM).
+
+Wallet
+
+A file that houses private keys. It usually contains a software client which allows access to view and create transactions on a specific blockchain that the wallet is designed for.
+
+
+