What's the difference between static and dynamic typing in programming?

Static typing checks variable types at compile-time, while dynamic typing checks them at runtime.

In more detail, static typing is a feature of programming languages where type checking is performed during compile-time as opposed to run-time. This means that the type of a variable is known at compile time. For example, in Java, which is a statically-typed language, you have to declare the type of a variable when you create it, and once it's declared, you can't change it to a different type. This can help catch errors early in the development process, as the compiler can spot type mismatches and other type-related errors before the program is run.

On the other hand, dynamic typing is a feature of programming languages where type checking is performed at run-time. This means that the type of a variable is checked only when the code is executed. Languages like Python and JavaScript are dynamically-typed, meaning you can change the type of a variable even after it's been defined, and no errors will be thrown until the code is run. This can make these languages more flexible and easier to use, especially for beginners, but it can also lead to unexpected errors if a variable's type is changed unintentionally.

In static typing, the type information is associated with the variable itself, whereas in dynamic typing, the type information is associated with the value that the variable references. This fundamental difference leads to a number of practical implications. For instance, statically-typed languages tend to be more verbose since they require explicit type declarations, while dynamically-typed languages are often less verbose but may require more testing to catch type-related errors.

In summary, the choice between static and dynamic typing depends on the specific needs and constraints of your project. Statically-typed languages can provide more safety and performance benefits, while dynamically-typed languages offer more flexibility and ease of use.