One of the methods search engines use to evaluate and rate content within a website or blog page is calculation of the ‘HTML to text ratio’. This ratio indicates whether most of the page’s content is HTML code or actual text content. The lower the ratio, the more important the text will seem to the engine. This is one reason to locate your CSS and JavaScript code in external files. Search spiders do not evaluate these external files as part of the ratio, meaning that the clean content that remains in the main file will be given more priority than if it were lost in a sea of extraneous code.