Cascading Style Sheets – in very basic terms, a list of style definitions for HTML tags. CSS gives you the ability to set colour, font size, margins, borders and many more attributes across a whole site with just one declaration. This gives the advantage of being able to change the site's design more easily. It also means that pages load quicker than traditional table-based layouts. CSS also results in a more accessible site as style declarations are stored separately from content.
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