A Web developer is a kind of programmer who specializes in the development of applications relating to the World Wide Web or distributed network applications, which typically run protocols like HTTP from a Web server to a client browser using associated programming languages like HTML/CSS, C#, Ruby and PHP to name a few. A Web developer is usually concerned with the back end or the programming aspect of creating a website or Web application and is not to be confused with a Web designer, who only deals with the aesthetics of a website or application, although many professionals have both skillsets