Our eyes are very receptive to the color red. Red is therefore frequently used as a signal color in advertising and traffic signs, and also in flags, standing for example for socialism (with hammer and sickle) or Switzerland (with a cross). In Switzerland, red as the national color was also a logical choice for the design of a corporate identity for Swiss Railways (SBB) and Swissair. Along with the contrasting non-colors of black and white, red can often be found next to its complementary color, green. While blood red is a deeply human color, red also symbolizes the heat of fire or the glow of embers. (Andres Janser)