javascript-timers

Question 1

What is a “callback” function?

Answer 1

a callback function is a function passed into another function as an argument, which is then invoked inside the outer function to complete some kind of routine or action.

Question 2

Besides adding an event listener callback function to an element or the document, what is one way to delay the execution of a JavaScript function until some point in the future?

Answer 2

you can use the setTimeout() method

Question 3

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

Answer 3

you can use the setInterval() method

Question 4

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

Answer 4

the default value is 0, it will run after the as soon as the current running code is done.

Question 5

What do setTimeout() and setInterval() return?

Answer 5

an numeric ID number of the timer.