DOM

DOM is a tree structure that browsers use to understand and represent a web page.
in this tree, each element is called a node.
- Document Node: This is the top-level node in the DOM and represents the entire HTML document.
- Element Node: This represents an HTML element, such as div, p, ul, etc.
- Attribute Node: This represents an attribute of an HTML element, such as id, class, src, etc.
- Text Node: This represents the actual text within an HTML element

so "manipulating the DOM" means modifying or exploring this tree structure of the web page.