A song is a piece of music with words that people sing. Songs combine melody (the tune you hum), lyrics (the words), and rhythm (the beat) into something that can express feelings, tell stories, or just be fun to sing along with.

Every culture throughout history has created songs. Ancient Greeks sang epic poems about heroes. Medieval troubadours traveled from town to town sharing songs about love and adventure. Today, people write songs about everything from heartbreak to video games to scientific discoveries.

Songs come in countless styles: lullabies that help babies sleep, patriotic anthems that bring citizens together, folk songs that preserve history, pop songs on the radio, and sea shanties that sailors once sang while hauling ropes. A song might make you want to dance, help you remember information (like the alphabet song), or move you to tears.

The word can also describe the musical sounds that birds make. When a robin sings its song at dawn, it's using a series of notes to mark its territory or attract a mate. Scientists have discovered that some birds actually learn their songs from their parents, much like humans learn language.

When something is sold for very little money, we say it went for a song, meaning it was practically given away.