1) The first commercially available digital camera, the Dycam Model 1, was introduced in 1990 and had a resolution of 376 x 240 pixels.

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

3) Antarctica is the coldest, driest, and windiest continent on Earth. It is also the highest, with an average elevation of about 7,545 feet (2,300 meters).

4) The process of impeachment involves charging a public official, such as a president or high-ranking government official, with misconduct and potentially removing them from office through a trial and vote by the legislature.