1) The first successful portable MP3 player, the Diamond Rio PMP300, was released in 1998 and could hold up to 60 minutes of music.

2) The Federal Reserve System, often referred to as the Fed, is the central banking system of the United States.

3) The concept of virtual reality (VR) involves creating a simulated environment that can be explored and interacted with using specialized headsets and input devices.

4) The musical "The Phantom of the Opera" has been running in London's West End since 1986, making it the longest-running musical in history.