Web design is the process of creating websites. It encompasses several different aspects, including webpage layout, content production, and graphic design. While the terms web design and web development are often used interchangeably, web design is technically a subset of the broader category of web development.
CSS is a plain text file format used for formatting content on web pages. CSS stands for Cascading Style Sheet and is used by web pages to help keep information in the proper display format. CSS files can help define font, size, color, spacing, border and location of HTML information on a web page, and can also be used to create a continuous look throughout multiple pages of a website. CSS files aid website programmers by allowing a single file which contains all display settings, as well as simplifying HTML by allowing for multiple page layout design.
A CMS is a software tool that allows you to create, edit, and publish content. While early CMS software was used to manage documents and local computer files, most CMS systems are now designed exclusively to manage content on the Web.
Web development is a broad term for the work involved in developing a web site for the Internet (World Wide Web) or an intranet (a private network). ... Among web professionals, "web development" usually refers to the main non-design aspects of building web sites: writing markup and coding.