'Yellow might be a simple colour—the third colour of the rainbow—but it means different things to different people. For some, it conjures up the image of daffodils, for others, the Kraft cheese singles wrapped in plastic that were the staple of every primary school kid’s lunchbox in the 1990s and early 2000s. For others still, it might be the doors of the Queensland Rail trains, ever slow to open, ever fast to close. In colour psychology, the right yellow can increase optimism, self-esteem, confidence, friendliness, creativity. However, the wrong yellow can result in feelings of fear, irrationality and anxiety.' (Introduction)