In addition to HTML, other markup languages support the use of CSS including XHTML, plain XML, SVG, and XUL.
Separation of formatting and content also makes it feasible to present the same markup page in different styles for different rendering methods, such as on screen, in print, by voice (via speech based browser or screen reader), and on Braille based tactile devices. CSS also has rules for alternate formatting if the content is accessed on a mobile device.
CSS is designed to enable the separation of presentation and content, including layout, colors, and fonts. This separation can improve content accessibility; provide more flexibility and control in the specification of presentation characteristics; enable multiple web pages to share formatting by specifying the relevant CSS in a separate .css file, which reduces complexity and repetition in the structural content; and enable the .css file to be cached to improve the page load speed between the pages that share the file and its formatting.
JavaScript is a high level, often just in time compiled language that conforms to the ECMAScript standard. It has dynamic typing, prototype based object orientation, and first class functions. It is multi paradigm, supporting event driven, functional, and imperative programming styles. It has application programming interfaces (APIs) for working with text, dates, regular expressions, standard data structures, and the Document Object Model (DOM).