The document discusses definitions and theories of happiness from various perspectives. It defines happiness as a feeling or emotion that can be positive like joy or contentment, and discusses two main types described in psychology: hedonic happiness focused on pleasure and pain, and eudaimonic happiness concerned with life satisfaction and fulfillment. The document also outlines factors that influence happiness like relationships, work, health and finances, and provides strategies for enhancing happiness including gratitude, optimism, kindness, and using personal strengths. World rankings of happiness are discussed, with Nordic countries typically ranking highest.