JavaScript Function Syntax A JavaScript function is defined with the function keyword, followed by a name, followed by parentheses (). Function names can contain letters, digits, underscores, and dollar signs (same rules as variables). The parentheses may include parameter names separated by commas: (parameter1, parameter2, ...) The code to be executed, by the function, is placed …

Jul 8, 2025 · Functions are one of the fundamental building blocks in JavaScript. A function in JavaScript is similar to a procedure—a set of statements that performs a task or calculates a value, but for a procedure to qualify as a function, it should take some input and return an output where there is some obvious relationship between the input and the output. To use a function, …

Jun 28, 2025 · Functions in JavaScript are reusable blocks of code designed to perform specific tasks. They allow you to organize, reuse, and modularize code. It can take inputs, perform actions, and return outputs.

Oct 14, 2022 · The function keyword goes first, then goes the name of the function, then a list of parameters between the parentheses (comma-separated, empty in the example above, we’ll see examples later) and finally the code of the function, also …

Summary Use the function keyword to declare a function. Use the functionName() to call a function. All functions implicitly return undefined if they don’t explicitly return a value. Use the return statement to return a value from a function explicitly. The arguments variable is an array-like object inside a function, representing function ...

A function is an independent block of code that performs a specific task. A function expression is a way to store functions in variables. In this tutorial, you will learn about JavaScript functions and function expressions with the help of examples.

Learn what are functions in JavaScript. Explore the basics of functions in JavaScript, including anonymous and arrow functions, and learn how to organize your code using functions.

A function is a block of organized, reusable code that is used to perform a single, related action. Functions provide better modularity for your application and a high degree of code reusing. Function Declaration A function declaration in JavaScript is a way to define a function. It’s also known as a function statement. The function keyword is used, followed by the name of the …

Jul 15, 2025 · The function* declaration creates a binding of a new generator function to a given name. A generator function can be exited and later re-entered, with its context (variable bindings) saved across re-entrances.

JavaScript functions are defined with the function keyword. You can use a function declaration or a function expression.