The colour blue brings up several thoughts; it could remind you of a clear sky during the day, a still ocean, or even someone you know with piercing blue eyes. The colour blue is the rarest occurring colour in the natural world which is why it has always been a sought-after colour in human history.
Blue can bring about feelings of calmness, and due to the non-aggressive nature of the colour blue, it is associated with tranquillity, serenity and orderliness. Due to the association with oceans, some people may find the colour blue soothing.
You may (or may not) have noticed that police officers, business people and general workforce uniforms are coloured in shades of blue. This is because the colour blue is also associated with trust and dependability, and creates an authoritative yet calming presence.