this assigment is on how to link js to html and to show if the code will run with the script ontop of the head instead of it been under
DOM is document obkect model,it is an interface to web page.and allows program to read and manipulatae page,content,structure and style The DOM is an object-based representation of the source HTML document. It has some differences, as we will see below, but it is essentially an attempt to convert the structure and content of the HTML document into an object model that can be used by various programs.
The object structure of the DOM is represented by what is called a “node tree”. It is so called because it can be thought of as a tree with a single parent stem that branches out into several child branches, each which may have leaves. In this case, the parent “stem” is the root element, the child “branches” are the nested elements, and the “leaves” are the content within the elements.