CSS holds for Cascading Style Sheet, Style defines how to present the HTML Elements. CSS is considered mostly to allow the partition of script substance writer by HTML content from script appearance, including elements such as the layout, colors, and font face, color and style. This division can develop ease of access the content, present more flexibility and manage in the design of presentation individuality, allow many pages to share designing, and decrease difficulty and duplication in the structural content.

Why CSS?

CSS Sheets downloaded only once and stored in cache memory, so pages will load easily and quickly. Using style sheet we have to manage layout and Web page Presentation. CSS gives efficiency in design and it is easy to work with.
CSS 1, CSS 2. CSS 3, and CSS 4 these are the versions of Cascading Style Sheet. CSS is divided into three types; there are Internal or Embedded Styles, Inline Styles and External Styles.

Internal or Embedded Styles are located inside the head tag of an exacting web page through the style tag.

Inline Style is used directly inside the HTML tag. We cannot use the Style builder to create the Inline style.

External Style is a Separate style page which is linked to the web page. So the styles are outside of the web page.