Jul 8, 2025 · 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 …

What is a Function? A function relates an input to an output. It is like a machine that has an input and an output. And the output is related somehow to the input.

When Should I Use a Function? If a part of your program does a specific task, you should create a function for it. It is especially useful to create a function if you need to run that code more than …

A JavaScript callback is a function passed as an argument to another function, which is then executed (or "called back") at a later point in time to complete a specific task.

Jul 8, 2025 · The Function() constructor, function expression, and function declaration syntaxes create full-fledged function objects, which can be constructed with new. However, arrow …

The concept of a function was formalized at the end of the 19th century in terms of set theory, and this greatly increased the possible applications of the concept. A function is often denoted by a …

Oct 6, 2025 · A function is a special relation or method connecting each member of set A to a unique member of set B via a defined relation. Set A is called the domain, and set B is called …

The simplest definition is: a function is a bunch of ordered pairs of things (in our case the things will be numbers, but they can be otherwise), with the property that the first members of the …

Jan 13, 2026 · Function, in mathematics, an expression, rule, or law that defines a relationship between one variable (the independent variable) and another variable (the dependent …

Uh oh, it looks like we ran into an error. You need to refresh. If this problem persists, tell us. A function is like a machine that takes an input and gives an output. Let's explore how we can …