Content is a combination of what the viewer sees (text, graphics, information, your logo, trademarks, videos, audio clips, icons, images, ads, opt-in or other user interface mechanisms, etc) as well as the layout, design (look and feel), control features and elements of a website.
Content Architecture interprets the goal of a website into a compelling viewer experience. With special attention to user interface, it schematizes and orders information to encourage easy navigation, direct action and interest. Content architects work with designers and developers to insure cohesiveness among the elements.