Rather than spending hours, days, weeks and months designing those pixel-perfect comps in Photoshop, a mainstay in a waterfall-oriented development process, designing in browser allows you to take whatever sketches and preliminary work you’ve conducted and enables you to jump right into the text editor and emerge with shippable code.
…There are many articles in the tech community that sing the praises of designing in browser — it’s future of web design, we should Kill Photoshop — to name a couple.