Js onload event usage tips _ basic knowledge

Window. load and window. onload does not mean to execute after the page is loaded. It depends on how you use it. The following example shows how to use it. If you are interested, refer to it. load and window. what does onload mean? I'm afraid you will answer me: "isn't this executed after the page is loaded ".
But the answer is not necessarily, depending on how you use it. Let's take a look at the example.
Example 1:

The Code is as follows:

Untitled