The human mind is highly responsive to visual stimuli, and colour is one of the major defining factors in that response. On both a conscious and subconscious level, colours convey and are thus important to consider when considering logo design.
Every colour, including black and white, has implications for logo design. In general terms, bright and bold colours are attention-grabbing but can appear brash. Muted tones convey a more sophisticated image, but run the risk of being overlooked. More specifically, particular meanings are ascribed to different colours in society.
See below what the various colours of the rainbow can evoke:
Red implies passion, energy, danger or aggression; warmth and heat. It has also been found to stimulate appetite, which explains why it is used in so many restaurants and food product logos ie Maccas. Choosing red for your logo can make it feel more dynamic.
Orange is often see as the colour of innovation and modern thinking. It also carries connotations of youth, fun, affordability and approachability.
Yellow requires cautious use as it has some negative connotations including its signifying of cowardice and its use in warning signs. However it is sunny, warm and friendly and is another colour that is believed to stimulate appetite.
Green is commonly used when a company wishes to emphasise their natural and ethical credentials, especially with such products as organic and vegetarian foods. Other meanings ascribed to it include growth and freshness, and it's popular with financial products too.
Blue is one of the most widely used colours in corporate logos. It implies professionalism, serious mindedness, integrity, sincerity and calm. Blue is also associated with authority and success, and for this reason is popular with both financial institutions and government bodies.
Purple speaks to us of royalty and luxury. It has long been associated with the church, implying wisdom and dignity, and throughout history it has been the colour of wealth and riches.
Black is a colour with a split personality. On the one hand it implies power and sophistication, but on the other hand it is associated with villainy and death. More mundanely, most logos will need a black and white version for use in media in which colour is not available – and there is currently a trend for bold monochrome logos and word marks.
White is generally associated with purity, cleanliness, simplicity and naiveté. In practical terms, a white logo will always need to stand in a coloured field to make it show up on a white background. Many companies will choose to have a coloured version and a white version of their logos; for example, the Coca-Cola word mark appears in white on its red tins and brown bottles but is used in red when needed on a white background.
Brown has masculine connotations and is often used for products associated with rural life and the outdoors.
Pink can be fun and flirty, but its feminine associations means it is often avoided for products not specifically targeted at women.
These associations are not rigid rules, of course, but they're worth keeping in mind as you make your colour choices. Remember that the overall impact of your logo design will depend not on the colours themselves but upon how these interact with the shapes and text.
Finally, don't put too much focus on colour choice. Consider that one in 12 of us suffer from colour blindness. Try to make sure your colour choice reinforces and enhances the design of your logo – but doesn't define it.