Closures
A closure is a programming concept where a function retains access to its lexical scope, even when the function is executed outside that scope. This means that the inner function can remember the variables and parameters of its outer function, allowing for more flexible and powerful code.
Closures are commonly used in languages like JavaScript and Python to create private variables or to maintain state in asynchronous programming. They enable developers to encapsulate functionality and create functions that can be reused with different contexts, enhancing modularity and reducing global variable usage.