1) The first commercially successful video game was "Pong," released in 1972 by Atari.

2) Oprah Winfrey is an American media mogul, television host, actress, and philanthropist. She is best known for hosting "The Oprah Winfrey Show," which became the highest-rated talk show in TV history, and for her influential role in the entertainment industry.

3) The Amazon rainforest produces more than 20% of the world's oxygen.

4) The Alps, located in Europe, are a popular destination for skiing, mountaineering, and hiking.