In biology, cell theory is a scientific theory which describes the properties of cells. These cells are the basic unit of structure in all organisms and also the basic unit of reproduction.
The doctype declaration should be the very first thing in an HTML document, before the <html> tag. The doctype declaration is not an HTML tag; it is an instruction to the web browser about what version of the markup language the page is written in. The doctype declaration refers to a Document Type Definition (DTD).
HTML - Font. The <font> tag provides no real functionality by itself, but with the help of a few attributes, this tag is used to change the style, size, and color of HTML text elements. The size, color, and face attributes can be used all at once or individually, providing users with the ability to create dynamic font styles for any HTML element.