Contratos inteligentes

The machinery underneath decentralised applications, for readers who want to understand it rather than just use it. This section covers what a smart contract is, how one is deployed, what a security audit does and does not prove, why immutability is simultaneously the core feature and the core hazard, and what upgradeability patterns really mean for who ends up in control. It also covers the failure modes that matter to ordinary users: bugs that execute faithfully, oracle manipulation, and the token approvals that quietly let a malicious site drain a wallet. Our scam-avoidance guide covers the approval mechanics in practical detail.