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What does "mutable" mean in programming?
mutable is one of the most common terms in software development. This guide explains what it means, how it is used in practice, and why it matters, with real examples from the developer world.
Definition
Describes a value or object that can be changed after it is created. In JavaScript, objects and arrays are mutable by default. Mutable state shared across a program can make bugs harder to track down.
Example
"const list = [1, 2, 3]; list.push(4); // list is mutable"
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