Some, like Andy Clarke, treat it as the biggest part of the design process, allowing the client to see flexible layouts, type, and rendering engine treatments on the fly as a design comes together; others, like me or Mike Kus, use it as an extension of our Photoshop work: initial design is done offline and is completed by filling in the gaps while in the browser. It’s certainly not my intention to write about the merits and pitfalls of designing in the browser here, but the key point is that if you don’t know how to write HTML and CSS, it’s an avenue that’s completely closed off to you. The design process can begin and end entirely in your graphics app, but because websites will not (and should not) look the same in every browser, the design will not actually be complete until it’s coded.