Another case of plagiarism is:
Short overview of what Bitcoin offers
Bitcoin is a strictly digital peer-to-peer currency, which operates on a decentralized, globally distributed network of computers, called nodes, freeing it from the control or oversight of any central authority, such as a government, corporation, or financial institution. Unlike traditional financial systems, which rely on central banks or financial intermediaries, Bitcoin's decentralized nature means it's not subject to single points of failure or control, creating a highly secure and robust system almost impervious against attacks or censorship, which paired with Bitcoin’s global accessibility, pseudonymity, ownership control, limited supply and borderless transactions render it especially valuable to people living under regimes or strict financial control.
How Bitcoin is able to be a decentralized, distributed network, built up of nodes that are able to work together, without needing to trust each other or a central party, through use of a mechanism called “emergent consensus”.
Bitcoin as a decentralized, distributed, and trustless network is achieved by having each node featuring its own copy of the blockchain, allowing it to operate independently from its peers and abling it to independently verify and validate transactions and blocks, as well as verifying the blockchain’s history and rules without having to trust its peers, while simultaneously adding redundancy to the network.
Nodes follow two sets of rules which allows the globally dispersed, individual network of nodes to achieve a consensus about the integrity, state and security of the blockchain, as well as the future assembly of it. Consensus within the Bitcoin network is also referred to as “emergent consensus”, emergent, because reaching consensus is an ongoing effort.
Nodes within the Bitcoin network follow two types of rulesets; one being policy rules, and the other being consensus rules.
Policy rules are a set of rules or conditions that are defined by the individual node, and can vary from one node operator to another. Policy rules can include decisions like setting a minimum transaction fee, blacklisting certain addresses, or defining spending limits. Policy rules are not enforced by the network as a whole, rather, they are enforced by the individual node operator or entity.
Consensus rules are the fundamental, unchanging rules that are hard-coded into the blockchain’s protocol, and are agreed upon by the entire network. Consensus rules determine how blocks are created, validated and added to the blockchain, and include parameters like the block size limit, the difficulty adjustment algorithm, the halving schedule, and the rules governing the issuance of new coins. Consensus rules are therefore strictly enforced by every node on the network, and every block or transaction that violates these rules will be rejected, which results in the non-compliant block or transaction not becoming part of the blockchain.
The “Proof-of-Work” algorithm as an integral part of the consensus-mechanism.
Transactions are verified against a node’s policy rules, and blocks are verified against the consensus rules, part of which requires blocks to provide a “Proof-of-Work”, which is created through use of an algorithm that attaches real-world costs to the creation of blocks, rewarding honest individuals with a block-subsidy and fees, and leaving malicious actors with the incurred costs, rendering it economically unviable to attack or manipulate the network.
The algorithm urges miners to “guess” an output that meets a specific set of conditions specified in advance, and add this output to the block, before broadcasting it to the network, leaving blocks without a Proof-of-Work to be rejected by the network for violating the consensus rules. The relative difficulty for meeting the set of conditions depends on the current difficulty, which is monitored and adjusted by the “difficulty-adjustment”, an algorithm used to adjust the specified conditions approximately every two weeks, or 2016 blocks, depending on the total hash rate available in the network, ensuring that about every ten minutes, a new block is found. The higher the difficulty, the more difficult it is to meet the specified conditions, and thus, the costlier it is to create a Proof-of-Work.
If someone were to try and broadcast a malicious block containing manipulated transactions, he’d have to enter the competition of finding a Proof-of-Work, add it to the block, and still get rejected because of the manipulated transactions contained by the block, leaving him with nothing but the incurred costs of guessing the Proof-of-Work.
The Proof-of-Work algorithm enables nodes to prove whether or not resources were used during the creation of the block, providing the ability to achieve consensus in a decentralized, distributed network without trust or need of control through a central entity, and ensures the security of the blockchain’s history through addition of a Proof-of-Work to every block in the chain. If someone wanted to change the contents of a past block, he’d have to not only create a new Proof-of-Work for the block in question, but for all subsequent blocks, too. An undertaking which nowadays would be so complex in terms of computational hardware, and so expensive in terms of energy, that the chance of success is nil, yet the chance of financial ruin is plenty, rendering the blockchain almost impervious to attacks or manipulation.
Plagiarized from
https://www.reddit.com/r/Bitcoin/comments/178ctt1/started_working_out_bitcoins_properties/, slightly rewritten:
Bitcoin operates on a decentralized network of computers, called nodes, making it free from the control or oversight of any central authority, such as a government, corporation, or financial institution. Unlike traditional financial systems, which rely on central banks or financial intermediaries, Bitcoin's decentralized nature means it's not subject to single points of failure or control, making it a highly secure and robust system, resistant against various forms of attack and censorship, rendering Bitcoin especially valuable to people living under regimes or strict financial controls. Each transaction on the Bitcoin network is validated by a globally distributed network of nodes, each respecting the same rules through the mechanism of emergent consensus, creating a trustless system which enables them to collectively verify the authenticity of transactions and the integrity of the blockchain without being dependent on the honesty or good intentions of a central entity.