Best practices

Ideally, web designers should strive to write code that is valid HTML and CSS. In doing so it makes it easier to correct problems, edit pages, or update pages. Additionally, keeping your HTML files and CSS files separate helps to make it easier to make changes. For example, having a separate CSS file allows for aesthetic changes to be made to the entire site rather than to just a single page. If CSS rules are included within a single HTML page, changes would have to be made to each and every page. The reasoning is that HTML should only be used for raw content and CSS be used to manipulate the content for aesthetic style. This is true for scripting files as well.^{[citation needed]}