Just like a city’s character can be defined by the organization of it’s urban blocks (see difference between NY and Paris for example), a portfolio can be defined by the organization of images on its pages. I am not suggesting that a square format or a grid format will define you as X versus someone else who will be defined as Y or Z by their use of linear or free-flowing formats. What I am saying is that the format will create a rhythm, a type of presentation, and will have some rules that may/ may not be appropriate for some projects or some target audiences. It is a very important factor to consider and try to determine early on.