Dynamic typing

Dynamic typing is a type system property in which variable types are checked at runtime rather than at compile time. Languages like Python, Ruby, and JavaScript are dynamically typed: a variable can hold an integer in one moment and a string the next, with type errors manifesting only when an operation is actually attempted. This contrasts with statically typed languages like C, C++, and Java, where type correctness is verified before execution.

The trade-off between dynamic and static typing maps onto a deeper tension in software design: flexibility versus guarantees. Dynamic typing allows rapid prototyping, concise expression, and polymorphism without explicit type declarations. But it defers error detection to runtime, where failures are more expensive and harder to diagnose. The rise of TypeScript — a statically typed superset of JavaScript — and Python's own gradual typing system (via type hints and mypy) suggest that the software industry is converging on a hybrid model: the convenience of dynamic typing for exploration, the safety of static typing for production.