A common misconception...
Blue colors are desperately trying to live down their reputation as being cold. It's a common reaction by many people who seem to repeat this piece of 'wisdom' when ever the subject of interior design is mentioned. But in their pale tones blues are known to have a calming effect. So use them where you want a restful atmosphere.
Its darker tones - royal or navy - are best used as accent colors. You can also use them in small rooms, or areas where you don't have to sit and look at them for too long.
On the other hand, pale blue looks good when put with touches of gold/yellow or coral, which give warmth to it.
A deep version, almost bordering on black, is often favored by boys for their bedrooms. Don't worry, they usually grow out of it!
There is some indication that it stimulates the intellect. This is why you sometimes find large country houses have libraries decorated in this color. Wishful thinking? You decide!
Blue color charts
