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What does "union" mean in programming?
union 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 that can hold one of several specified types. In TypeScript a union is written with a pipe: string | number. In C and C++ a union is a memory structure where all members share the same address.
Example
"type ID = string | number; // ID can be either a string or a number"
Related terms
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