Type system

In computer science, a type system defines how a programming language classifies values and expressions into types, how it can manipulate those types and how they interact. A type indicates a set of values that have the same sort of generic meaning or intended purpose (although some types, such as abstract types and function types, might not be represented as values in the running computer program). Type systems vary significantly between languages with, perhaps, the most important variations being their compile-time syntactic and run-time operational implementations.
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