What is the CSS box model?

The CSS box model is a box that wraps around every HTML element. It consists of: margins, borders, padding, and the actual content.

What is the difference beween margin and padding?

Margin properties are used to create space around elements, outside of any defined borders, and padding is used to generate space around an element's content inside of an defined borders.

How is the total height and width of an HTML element determined?

The total height and width of an HTML element is determined by the person writing the HTML code.

Explain this CSS property: padding: 25px 50px

The top and bottom paddings are 25px. The right and left paddings are 50px.