Blue expresses eternity and freedom. Among the cool colors, blue is the main color and it is also one of the most commonly used color. The blue color of peace and quiet is used in various tones, especially when painting sea, sky and horizons. It creates a calming effect in people. Blue and light blue painted environments increase productivity and performance. Underlining the notes you read with a thick blue pencil makes it easy to remember what is read. I guess many people have not thought why blue colored pencils are preferred in the world. Written with a blue pen is faster and more permanent in memory. In personality analysis of those who prefer blue color, we see that these people are tolerant, agreement-oriented and seeking peace. They are reconciled with the environment and themselves. They are patient and meticulous. They are also very self-sacrificing.