Bitcoin (BTC) Υπολογιστής

Emerging from the quiet of a 2008 whitepaper and going live in January 2009, Bitcoin is a decentralized, peer-to-peer digital currency that replaces central authority with open rules enforced by time, computation, and global consensus; it anchors transactions in a public blockchain where miners perform proof-of-work using the SHA-256 algorithm, competing to append blocks roughly every ten minutes and securing the network through vast aggregated hash power, with incentives delivered as a block subsidy plus transaction fees that together form miner revenue. The issuance is programmatic and finite: a hard cap of 21 million coins introduced via mining, with the subsidy halving approximately every four years (notably in 2012, 2016, 2020, and 2024), which slows supply growth and underpins a deflationary profile designed to resist debasement; difficulty adjusts every 2,016 blocks to keep block intervals steady regardless of swings in mining power. Bitcoin’s ledger uses a UTXO model and a limited, purpose-built scripting language, and its security rests on independently run full nodes that validate every rule-block size and weight limits, signature correctness, and consensus constraints-making changes possible only through broad agreement and carefully staged upgrades, often via soft forks proposed as Bitcoin Improvement Proposals; major upgrades such as Segregated Witness in 2017 improved transaction malleability and capacity, while Taproot in 2021 introduced Schnorr signatures and more private, efficient spending paths. On-chain throughput is intentionally constrained, which creates a fee market during congestion and has spurred development of second-layer solutions like the Lightning Network for fast, low-cost payments, alongside sidechains and other scaling experiments; common address formats include legacy, P2SH, and Bech32. Transactions are pseudonymous rather than fully anonymous, as flows are visible on the public ledger and can be linked through behavioral patterns, yet privacy can be enhanced with best practices and emerging tooling; settlement finality strengthens with additional confirmations as the cost to reorganize history compounds. Bitcoin’s energy-intensive proof-of-work-contrasting with proof-of-stake systems adopted elsewhere-anchors security in physics and capital, driving ongoing debates over environmental impact, energy mix, and the role of miners in grid flexibility, with the network demonstrating resilience through geographic shifts such as the post-2021 redistribution of mining activity. Over time, Bitcoin has evolved from an experiment to a widely recognized store-of-value narrative-often called digital gold-serving as the benchmark for the broader crypto ecosystem, influencing altcoin cycles and market structure, while institutional custody, regulated investment products, and even national-level experiments have broadened its reach; its first-mover advantage, robust security model, and simple, transparent monetary policy keep it a reference point for innovation, governance, and risk in an industry that often orbits its slow, deliberate cadence.