Cryptocurrencies do not exist in isolation — they are the product of several converging technologies that together enable decentralised, secure, and transparent digital finance (Tapscott and Tapscott, 2016).
At the core of most cryptocurrencies is blockchain technology — a distributed ledger that records transactions in chronological, tamper-resistant blocks. Each block contains a cryptographic hash of the previous block, creating an immutable chain. This eliminates the need for a central authority to validate transactions (Nakamoto, 2008).
Public-key cryptography underpins cryptocurrency wallets and transactions. Users hold a private key (kept secret) and a public key (shared openly). Transactions are signed with the private key and verified by the network using the public key, ensuring authenticity without revealing the private key (Diffie and Hellman, 1976).
Introduced by Ethereum, smart contracts are self-executing programs stored on the blockchain that automatically enforce the terms of an agreement when predefined conditions are met (Buterin, 2014). They power decentralised finance (DeFi), NFTs, and decentralised autonomous organisations (DAOs).
DeFi platforms use smart contracts to replicate traditional financial services — lending, borrowing, trading — without intermediaries. Protocols such as Uniswap, Aave, and Compound have collectively managed billions in assets (DeFi Pulse, 2024).
AI is increasingly integrated with crypto — from algorithmic trading bots and fraud detection to AI-driven blockchain analytics platforms such as Chainalysis (Chainalysis, 2024).
Cryptocurrencies like IOTA are specifically designed for machine-to-machine micropayments in IoT ecosystems, enabling autonomous devices to transact without human intervention (IOTA Foundation, 2024).