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

2) The first successful consumer digital camera, the Apple QuickTake 100, was released in 1994 and had a resolution of 640 x 480 pixels.

3) The Mona Lisa, painted by Leonardo da Vinci, is one of the most famous and valuable artworks in the world.

4) Dwayne "The Rock" Johnson is an American actor, producer, and former professional wrestler. He has become one of the highest-paid actors in Hollywood, known for his roles in films such as the "Fast & Furious" franchise, "Jumanji," and "Moana."