Higher-order functions are a fundamental concept in programming, particularly in functional programming paradigms. A higher-order function is defined as a function that either takes one or more functions as arguments or returns a function as its result. This allows for a more abstract and flexible way to handle operations, enabling developers to create more reusable and modular code.

In many programming languages, including Python and JavaScript, higher-order functions are commonly used. For example, functions like map(), filter(), and reduce() are classic examples of higher-order functions that operate on collections of data. They allow you to apply a function to each element in a list, filter elements based on a condition, or reduce a list to a single value, respectively ²³.

Additionally, higher-order functions can enhance code readability and maintainability by reducing boilerplate code and promoting the use of anonymous functions or lambdas, which are functions defined without a name ³⁴.

If you have more specific questions about higher-order functions or their applications, feel free to ask!