CSS, or Cascading Style Sheets, is a way to decide how an HTML document will appear on the browser. It controls the look and feel of the HTML documents. The primary function of the CSS is to separate text displayed on a web page (created in HTML code) and information that describes how to display the text (which is defined using CSS).
It is important to use CSS for ease of coding and saving the time and energy, since we may want the content of your web page to change frequently but not the design/layout. It is a standard of the World Wide Web Consortium (W3C), which is an international Web standards consortium. CSS provides defined control for spacing, alignment, and positioning of content without relying on the necessity for layout tables or frames. Font, style, color, and font size can all be manipulated using CSS as well.
There are several benefits of CSS. First, it is easier to load a web page with CSS. Second, it allows placing the elements anywhere in the web page. Third, it offers more control to the page structure. It also adds flexibility to the web pages. CSS can be written separately so it is only needed to download it once – in the external style sheet document. When surfing the rest of the site the CSS will be cached on the computer, and therefore speed up the loading time of the webpage.