What is Web Design?
The process of conceptualization, modeling, planning and execution of electronic media content delivery through the World Wide Web in a language that can be interpreted by a Web browser and uses graphical user interface is known as Web design.
A Web site is the final output of a Web design. The Web site sits on a Web server where electronic files are stored. The Web site presents the contents and interactive features or interfaces to the end user in the form of Web pages. How the information requested is displayed to the user is par of the Web design process. Additional controls are imbedded in order to display more complex media like animations, sounds and other forms.
Source: Wikipedia.org