Definition
Information is the resolution of uncertainty. It is a measure of the constraints that a specific state or signal imposes on a set of possibilities. In its most irreducible form, information is a “difference that makes a difference” (Gregory Bateson), representing the structural or logical content of a system.
Why It Matters
Information is the “third pillar” of the universe, alongside matter and energy. It is the currency of intelligence, the blueprint of life (DNA), and the foundation of the digital economy. Understanding information—how it is captured, stored, corrupted, and used—is the key to mastering any complex system, from AI alignment to personal learning.
Core Concepts
- Signal vs. Noise: Information (signal) is the meaningful pattern; noise is the random variance that obscures it.
- Entropy: The measure of missing information or disorder. In
[Information Theory](information-theory.md), higher entropy means higher uncertainty and thus more information gained when that uncertainty is resolved. - Substrate Independence: Information is not the medium that carries it; the same data can exist in a book, a brain, or a bit.
- Physicality of Information: Information is physical; its erasure or manipulation requires energy and generates heat (Landauer’s Principle).
- Compression: The process of reducing the number of bits required to represent a signal by identifying its internal regularities.