Hash
Um identificador criptográfico de tamanho fixo criado a partir de dados de entrada variáveis.
Hashing is used throughout computer science for data indexing and retrieval, but in blockchain, it is the bedrock of security. It allows the network to verify the integrity of blocks and transactions. For instance, Bitcoin uses the SHA-256 algorithm to secure its ledger. Because hashes are one-way, they allow for 'Proof of Work'—where miners must find a specific hash that meets a difficulty target, proving they expended computational energy without revealing the secrets behind the data.
graph LR
Center["Hash"]:::main
Pre_cryptography["cryptography"]:::pre --> Center
click Pre_cryptography "/terms/cryptography"
Rel_encryption["encryption"]:::related -.-> Center
click Rel_encryption "/terms/encryption"
Rel_mathematics["mathematics"]:::related -.-> Center
click Rel_mathematics "/terms/mathematics"
classDef main fill:#7c3aed,stroke:#8b5cf6,stroke-width:2px,color:white,font-weight:bold,rx:5,ry:5;
classDef pre fill:#0f172a,stroke:#3b82f6,color:#94a3b8,rx:5,ry:5;
classDef child fill:#0f172a,stroke:#10b981,color:#94a3b8,rx:5,ry:5;
classDef related fill:#0f172a,stroke:#8b5cf6,stroke-dasharray: 5 5,color:#94a3b8,rx:5,ry:5;
linkStyle default stroke:#4b5563,stroke-width:2px;
🧒 Explique como se eu tivesse 5 anos
🌍 O hash é como a 'impressão digital' de um ficheiro. Se alterar um pixel numa imagem, a impressão digital muda totalmente.
🤓 Expert Deep Dive
A resistência a colisões garante que é virtualmente impossível dois inputs diferentes gerarem o mesmo output.