Need help to understand this Javascript snippet of code :)

Hey erdrag,

This first line selects each element on the page and puts it into a NodeList/HTMLCollection (depending on the browser). This is an array-like object that gets each element by the tag name and stores them into this object.

var nodes = document.getElementsByTagName('video');

The second line takes the NodeList/HTMLCollection received from the variable nodes and converts it into an array object. The call is made to nodes which is used with the slice function to return a copy of an array. Since the original object was not an array, we have to use "Array.prototype" in order to convert it into an array.

var videos = Array.prototype.slice.call(nodes);

This final line iterates over each object in the array. The variable in the function call video is used as a substitute for each individual element stored in the array. And then you are setting each video element to a volume of 0.5 or 50%.

videos.forEach(function(video) {
  video.volume = 0.5;
});

Does that make more sense?