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What does "optional" mean in programming?
optional 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
A type or parameter that may or may not have a value, often expressed as T | undefined. In TypeScript, a property marked with ? is optional. In Swift and Kotlin, Optional is a built-in type that wraps a value or contains nothing.
Example
"function greet(name?: string) { } // name is optional — may be undefined"
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