1) Serena Williams, an American tennis player, has won a total of 23 Grand Slam singles titles, making her one of the most successful players in the history of the sport.

2) A newborn kangaroo is about 1 inch (2.5 centimeters) long and weighs less than a gram.

3) Political campaigns involve strategic activities, such as advertising, public appearances, and grassroots organizing, aimed at promoting a candidate or political party and gaining support during elections.

4) The first computer mouse was invented by Douglas Engelbart in 1964 and consisted of a wooden shell and two metal wheels.