Themes are an extension of another idea, like Master Pages, that has kept developers working long hours. How do you quickly change the look and feel of your site for different users or usages? This is where Themes come in. Themes can be thought of as a container where you store your style sheets, images, and anything else that you may want to interchange in the visual pieces of your site. Themes are folders where you put all of these pieces to group them together. While one user may be visiting your site and seeing it one way, another user can be viewing the exact same site, but get a completely different experience.
Let's start off by enabling our site to include the use of Themes. To do this, right-click on the project in the Solutions Explorer, select Add ASP.NET Folder, and then choose Theme from the submenu:
The folder will default to Theme1
as its name. I'd suggest that you name this something friendlier though. For now, we will call the Theme as "SimpleCMSTheme". However, later...