Colors invoke meaning, sometimes before words are even written or read. A large part of successful web design involves choosing the right colors for a website; however, color decisions involve many different factors. Color preference is subjective, different shades of colors can express different meanings, and color meaning can also differ between cultures and countries. The color meanings supplied below are generalizations which may be helpful when designing websites.
Red
Red is a powerful color which universally signals danger and emergencies. Many fire trucks are colored all red and their flashing lights are usually all red as well. Other symbols of red in the world are red stop lights and stop signs. In websites and user interfaces, red may be used in error messages, object deletion icons, and within dials or instruments to illustrate max resource usage.
Red may also be used to illustrate passion and love such as hearts, red roses, and related Valentine's Day symbols.
Web designers normally use red sparingly to prevent it from overpowering the entire website.
Blue
Many surveys point to blue as the most favorite color of both men and women. Blue is also very prevalent in nature from expansive blue skies to encompassing blue oceans. Blue is often seen as a color of trust and stability and is a popular color for many large business logos and websites. Besides red, the flashing lights for many police cars include the color blue.
In design, some of the largest companies (Ford, GM, GE, IBM, Walmart, etc) use blue in their logos or prominently within their websites as backgrounds, text, etc.
Green
Green normally symbolizes nature and harmony. Eco-friendly websites and icons (recycling triangle arrows, variously shaped leaves, etc), lawn and plant care companies and products, and sustainable energy websites usually contain varying shades of green.
Pink
Pink is the color most universally associated with femininity and is typically used on websites or products targeting the female demographic or having a feminine quality. Pink may also be used to represent love in a lesser sense than red. The most common meaning assigned to pink is nurturing.
Yellow
The color yellow has many different meanings, but is generally considered upbeat. Sunny days and rays of sunshine speak to the positive, cheerful, and high energy meanings attached to the color yellow. Yellow is also used as informational road signs (yield, pedestrian crossing, slippery when wet, etc) and similarly within user interfaces as informational messages.
Like red, certain shades of yellow may be very overpowering and are normally used sparingly within web designs.
White
White symbolizes simplicity, cleanliness, and purity. White is seen many places, but some notable uses are within the medical profession (hospitals, ambulances, traditional nurse uniforms and doctor lab coats.
For web design, many websites use black or dark text on white backgrounds to create high contrast, readable text. Some designers argue white backgrounds create glare and are harsh on the eyes.
Black
Black is often associated with elegance, sophistication, and formality. In web design, black backgrounds are often seen on many creative, artistic websites from photography to dance studios.
Within compositions, it is interesting to note that since pure black is not supposed to occur naturally, using a pure black anywhere may seem unnatural. As an example, for dark areas such as shadows underneath text or objects (drop shadows), instead of choosing black, a more realistic color choice would be a darker shade of the bottom color.