Designing for the web and designing for print can be very different. Of course the is the obvious rgb and cmyk. When designing both you have to be concerned with the size of your final production, be it screen or paper. web design can be a bit more difficult, especially if you will not be person actually writing the code. Layout is important in both media and you have to consider eye flow, however in web design you have less to to grab the attention of the user so in that aspect layout in web is more important.