we are going to learn how can we delay a function in JavaScript. Whenever we want to call a function after a specified amount of time than we use the delay function in JavaScript.

To provide delay in JavaScript function we use a global window object named as setTimeout(). This function allows us to provide a specific delay before executing a function.

Let’s deep down into some of the functionalities, syntax and many other things of setTimeout() function. The setTimeout() method mainly require two one is the function which we need to execute with some delay and the other argument is the time for which we want to delay the function.

Syntax

Syntax to delay a function in JavaScript is given as −

When function declared inside the setTimeout() method:
setTimeout ( function(){function_body}, time in milliseconds);
   or
When function declared outside setTimeout() method:
function function_name();
setTimeout(function_name, time i
n milliseconds);

As the function declared in the setTimeout() method is anonymous so we can also remove the function keyword and replace it with the arrow function like shown below −

setTimeout(()=>{function_body}, time in milliseconds);