ASCII
Un estándar de codificación de caracteres de 7 bits que asigna 128 caracteres a valores numéricos (0-127).
El diseño de ASCII facilitó operaciones a nivel de bits: la única diferencia binaria entre 'A' (65) y 'a' (97) es el sexto bit. Hoy en día, los primeros 128 caracteres de Unicode son una copia exacta de la tabla ASCII original.
graph LR
Center["ASCII"]:::main
Rel_unicode["unicode"]:::related -.-> Center
click Rel_unicode "/terms/unicode"
Rel_binary["binary"]:::related -.-> Center
click Rel_binary "/terms/binary"
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;
🧒 Explícalo como si tuviera 5 años
Las computadoras solo entienden números, no letras. ASCII es un código secreto que todo el mundo usa: 'Si ves el 65, dibuja una A mayúscula; si ves el 32, haz un espacio'.
🤓 Expert Deep Dive
ASCII verdadero es estrictamente de 7 bits. Los caracteres de control (0x00-0x1F) fueron diseñados para teletipos mecánicos (ej. CR y LF). El ASCII extendido fragmentó los estándares de 8 bits (ej. Windows-1252) hasta que UTF-8 unificó todo, manteniendo una compatibilidad retroactiva total con ASCII.
❓ Preguntas frecuentes
Why is ASCII only 7 bits instead of 8 bits?
When ASCII was developed in the 1960s, a 7-bit code was sufficient to represent the English alphabet, numbers, and punctuation. The 8th bit in a byte was often reserved as a parity bit to check for errors during data transmission over unreliable networks.
What is the difference between ASCII and Unicode?
ASCII is limited to 128 characters and primarily supports English. Unicode is a massive standard designed to support over 149,000 characters across almost every language in the world, plus emojis. However, the first 128 characters of Unicode are identical to ASCII.
What are Extended ASCII codes?
Since computers use 8-bit bytes, the 7-bit ASCII standard left the 8th bit unused (values 128-255). Different companies (like IBM, Apple, and Microsoft) used these extra 128 slots for foreign letters and drawing symbols, creating incompatible 'Extended ASCII' code pages.