javascript-timers

Question 1

What is a “callback” function?

Answer 1

A function that is passed to another function to be called inside the function it was passed to.

Question 2

What is one way to delay the execution of a JavaScript function until some point in the future?

Answer 2

Using the setTimeout() function with the function to be delayed as the first argument and the time to delay it in milliseconds for the second argument.

Question 3

How can you set up a function to be called repeatedly without using a loop?

Answer 3

The setInterval() method can be used with the first argument being the function to repeatedly call, the second argument being the interval delay.

Question 4

What is the default time delay if you omit the delay parameter from setTimeout() or setInterval()?

Answer 4

The default time delay is the parameter is omitted is 0 milliseconds, which calls the function immediately.

Question 5

What do setTimeout() and setInterval() return?

Answer 5

They return the “timeoutID” which is a positive integer value that identifies the timer and can be passed to clearTimeout() to cancel the timeout or stop the interval.