Harold Edgar  NIEBUHR

 1921 - Charles Strite of Minnesota patents the pop-up toaster.

 1923 to 1927 - Television is invented (Vladimir Kosma Zworykin (Russia), Philo Taylor Farnsworth (United States))

 1927 - The aerosol can is invented (Erik Rotheim, Norway)

 1928 - Sliced bread (bread slicing machine) is invented by Otto Frederick Rohwedder (United States)

 1930 - Scotch tape is invented (Richard Drew (3M), United States)

 In 1930, on February 18, Pluto was discovered by astronomer Clyde Tombaugh at the Lowell Observatory in Flagstaff, Arizona, marking a significant milestone in the study of our solar system.

 1931 - The paper towel is invented (Arthur Scott, United States)

 1934 - The metal beverage can is invented (American Can Co., United States)

 1935 - The snowmobile was invented by Joseph Bombardier (Quebec, Canada)

 1938 - The ballpoint pen is invented (Lazlo Biro, Hungary)

 1938-1944 - Sunscreen is invented (Franz Greiter, Switzerland and Benjamin Green, United States)

 1938 - October 27 - Du Pont announces a name for its new synthetic yarn: nylon.

 1940 - April - 1st electron microscope demonstrated (RCA), Philadelphia, Pennsylvania, USA

 1945 - The atomic bomb is invented (J. Robert Oppenheimer, et al., United States)

 The microwave oven was invented accidentally in 1945 by Percy Spencer, a Raytheon engineer. While testing a magnetron, he noticed microwaves melted a candy bar in his pocket. Experimenting further, he discovered microwaves could cook food quickly. Raytheon patented the process, and by 1947, they built the first commercial microwave oven, called the 'Radarange.' Initially used in commercial settings, microwaves becomes affordable for home use by the 1960s and 1970s, revolutionizing cooking.

 1948 - Velcro is invented (George de Mestral, Switzerland)

 1968 - The ATM is invented (Don Wetzel, United States)

 The cell phone was invented by Martin Cooper of Motorola. On April 3, 1973, he made the first handheld mobile phone call with the Motorola DynaTAC. This device weighed 2.5 pounds and was 10 inches long, offering 30 minutes of talk time and requiring 10 hours to charge. The first commercial cell phone was released in 1983, revolutionizing communication and leading to the modern smartphones we use today.

1981 - June 5 - First reported case of AIDS (Acquired Immune Deficiency Syndrome)

 1982 - The camcorder is invented (Sony Corp., Japan)

 1983 - The laptop computer is invented (Radio Shack Corp., United States)

 1989 - The World Wide Web is invented at CERN (Tim Berners-Lee, UK)