CSS stands for Cascading style sheet, It is a style sheet which makes the webpage to look more attractive Using CSS, you can control the color of the text, the style of fonts, the spacing between paragraphs, how columns are sized and laid out, what background images or colors are used, layout designs,variations in display for different devices and screen sizes as well as a variety of other effects.
CSS is easy to learn and understand but it provides powerful control over the presentation of an HTML document. Most commonly, CSS is combined with the markup languages HTML or XHTML.
Why to use CSS
CSS is used to define styles for your web pages, including the design, layout and variations in display for different devices and screen sizes.