Countries of the World

Beneath the city of Cincinnati, Ohio is a huge labyrinth of tunnels and stations. The subway system was proposed in the 1910s as an upgrade of the streetcar system. Construction was interrupted in the turbulent years that followed, and never resumed because of inflation and politics.

There are over 300 million active Twitter users, making it one of the most popular social media platforms. Every minute, an average of 350,000 new tweets are posted on Twitter! The hashtag was introduced into the digital world in 2007 by Chris Messina. There were doubts the hashtag would catch on, with many believing it appeared too techy. Needless to say, they were wrong!

If you like fish, think about this! Farm-raised salmon is usually white, so salmon farmers add carotenoids, a type of plant pigment, to the fish feed to produce the natural pink color that wild salmon exhibit.