CSS (Cascading Style Sheets)/ Definition /CSS is a style sheet language used to control the presentation and layout of web pages written in HTML and XHTML.Related Glossary TermFrontend DevelopmentFrontend Development focuses on building and optimizing the visual and interactive aspects of websites or applications that users interact with directly.UI DesignUI Design focuses on creating intuitive and visually appealing interfaces that facilitate user interaction and enhance the overall user experience.Web DevelopmentWeb Development encompasses the design, creation, and maintenance of websites and web applications, including coding, scripting, and content management.