1) The World Wide Web, developed by Tim Berners-Lee in 1989, revolutionized the way information is accessed and shared on the internet.

2) The first sound film, "The Jazz Singer," was released in 1927 and marked the transition from silent movies to "talkies."

3) The speed of light is approximately 299,792,458 meters per second.

4) The Great Wall of China is not visible from space without aid, contrary to popular belief.