JS Timers

Question 1

What is a “callback” function?

Answer 1

It is a function passed in through another function as an argument

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

Use setTimeout( ) function

Question 3

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

Answer 3

Use setInterval( ) function

Question 4

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

Answer 4

0 (zero)

Question 5

What do setTimeout( ) and setInterval( ) return?

Answer 5

<b>setTimeout( ):</b> The returnedtimeoutIDis a positive integer value which identifies the timer created by the call tosetTimeout( )
<b>setInterval( ):</b> The returnedintervalIDis a numeric, non-zero value which identifies the timer created by the call tosetInterval( )