Music moves, music soothes and most important, music can improve your mood. Press play on these happy songs for a boost of cheer. The power of music is no joke—it can affect our mind, body and mood.

On Thursday, at the stroke of midnight, pop impresario Pharrell Williams debuted the video for his new single, “Happy.” It’s 24 hours long. The video, available for streaming on 24hoursofhappy.com, ...