You don't need to be a designer to understand the impact that colour can have on first impressions.
Whether it's the eponymous woman in red (from Little Red Riding Hood to Number Six, the dangerously seductive Cylon), or the allure of a wide expanse of blue (open skies from our ancestral savannah), the power of colour has long been documented in our offline world.
Although colour meanings can vary dramatically from culture to culture, if I asked you to think of a sexy, hot, aggressive colour, chances are you'd think of red. And if I asked you to call to mind a soothing, cool colour, you might think of blue. It's a simple association exercise, but one that hints at what a growing body of research is discovering: that colour can have a profound influence on our emotional, psychological and even physiological state.
Online, the impact is no less striking. The difficulty is finding a comprehensive, silver-bullet theory that realistically covers effective colour use, simply because the reality is far too complex to be reduced to such terms. The fact is that when it comes to persuasive colour use online, there are a multitude of variables you must consider if you are to communicate your message persuasively.
Everything from your cultural context (such as your age, ethnicity and gender) to your psychological makeup (learned associations) can influence the way in which you interpret and respond to colour. And with an increasingly global audience, knowing which colours to use when designing a website can be tricky at best.
There are a few rules of thumb you can follow, however.
For instance research has shown that using blue as the predominant colour for a website can elicit feelings of trust and security, which may be why it has become de riguer for so many financial institutions (especially given the current economic climate). What you may not know is that the colour blue can also warp our sense of time, making websites on slow connection speeds appear to load more quickly.
Yellow, on the other hand, is best avoided in web design, especially when considering it as the dominant colour for e-commerce sites - it's one of the few colours that appears to be ubiquitously disliked regardless of culture or creed.
There are of course always exceptions, and when it comes to designing for a particular audience your best bet will always be to do your research first and reflect the preferences of your target market. But whatever your message, one thing is certain - colour has a powerful way of communicating meaning.
Getting that meaning right is up to you.
Nathalie Nahai is an award-winning speaker, Web Psychologist, and author of 'Webs of Influence: The Psychology of Online Persuasion'.