javascript - difference between setTimeout() and setInterval()

i am trying to move a small div along a big div in the y-direction according to how much i scrolled down the page.but i've found that using setTimeout() and setInterval() gives two completely different results.actually setInterval() hanged by browser several times .what is the basic difference between the two function??

Answer

setTimeout executes the function once on a time out. setInterval executes the function repeatedly on and interval

https://developer.mozilla.org/en-US/docs/Web/API/Window.setTimeout
https://developer.mozilla.org/en-US/docs/Web/API/Window.setInterval