"Consistency is one of the most powerful usability principles: when things always behave the same, users don’t have to worry about what will happen. Instead, they know what will happen based on earlier experience."
Jakob Nielsen has become the Ultimate Champion of nerding-out about usability and the crossover between design and web development. In this blog post, which reads kind of list a list of religious commandments or a vaguely threatening to-not-do list, Nielsen points out the importance of consistency in design. It’s a good chunk of advice to hold on to when developing a portfolio or creating new work — you’re audience will be more receptive to what they’ve come to know and love about you if you stick to a few key elements in your work.