An extremely broad genre of music. Pop music consists of catchy melodies, infectious beats, polished instrumentals, and usually a calculated image/vision to go along with it and promote it. "Pop music," as a genre, isn't to be confused with the term, "popular music," which could be music from any genre that has garnered mainstream attention or adoration. Many works of pop music also never gain widespread popularity. Pop music is commonly structured in a verse-bridge-chorus-verse-bridge-chorus-middle 8-chorus form, but there are numerous exceptions to this standard, but pop music always has a catchy and polished sound to it that is intended to appeal to the public at large. Although, at times, pop music can have a "unique" sound to it that instantly will make one label it as "pop," pop music often heavily borrows from other genres of music, creating subgenres such as: dance pop, teen pop, bubblegum pop, r&b pop, pop rap, country pop, electropop, etc. The one characteristic that sets these subgenres away from the genres they borrow from is, again, a catchy, structured, and polished sound.
Pop music is also often maligned by music elitists and critics. But, the one thing you have to remember is that pop music is mostly intended to be fun and exciting, not some deep emotional work of art; although pop music can be deep and emotional at times, contrary to popular notion.
Examples of Pop Music and its stars:
... and the list goes on...