CSS is a special language that is used for HTML content styling. With the help of CSS, we can configure how HTML elements will be displayed – their color, size, position, border, background, etc.
The history of CSS started in mid 90s, and this language keeps developing nowadays. Before this style sheet language appeared, all the HTML properties were contained within the HTML markup. One had to describe each element inline to style a document – this was easily solved by CSS.
CSS is used to separate the HTML content from the representation rules to make it easier to maintain the content style in a centralized manner. Basically, all the style info is contained in another file. This makes the HTML code so much lighter and easier to read and edit.
CSS offers a lot of possibilities of working with big amounts of content. For example, with CSS Counters, you can quickly change the appearance of all lists, paragraphs, tables, and other elements that have repeated tags within them.
As CSS is used to fulfill many specific design related tasks, there’s a lot of information on the Internet about various CSS tricks, workarounds, and life-hacks. If you want to become a CSS pro, then you should never stop learning new things about this special language. As an example of what CSS can do, check out this article on Advanced Autonumbering Techniques.
CSS is used in many help authoring tools granting users deeper control over content design – you can fine-tune the way your online documentation looks using CSS. The idea behind this is that working with CSS directly, you get as much freedom in creating the design you wish as possible. ClickHelp is a great example of software for technical writing that fully supports CSS editing of user guides.
The CSS specifications are maintained by a special organization – the World Wide Web Consortium (W3C). To learn CSS starting from the basics, you can try out this tutorial on the W3Schools.com website: CSS Tutorial