The process of planning and creating a website is called Web Design. The work involves using text, images, digital media and interactive elements to produce a page as seen on a browser. The job of a web designer includes conceptualization, planning, post-production, research, advertising as well as media control that are applied to the pages within the site and these days, on mobile applications as well. HTML and CSS knowledge is important in web designing.
Useful Information on Web Design & Development