The world's population is expected to have hit a milestone today reaching 7 billion people. If there's something a bit alarming to you about this number it may be that you remember us reaching 6 billion just 12 years ago back in 1999.
National Geographic has been doing a year long series about a planet with 7 billion people. The above video from the series attempts to put the number in some perspective.
Viewsoftheworld.net has this great visualization illustrating how the distribution of growth has been changing over the past several decades.
