what are the “for” and “event” attributes of the script tag (Javascript,HTML)

Question

In a web application I\'ve inherited at work which was written about 10 years ago I\'ve noticed the following code snippets repeatedly used:

Answer 1

for attribute is for the element name in for attribute like for="element1" and event attribute is for event handling like even onclick, onmouseover etc for that elements.

For example if you add Onclick event then onclick event works on element which name you entered in for attribute.