1) The first successful human heart transplant was performed by Dr. Christiaan Barnard in 1967.

2) The human body contains enough carbon to make over 9,000 pencils.

3) A single bolt of lightning can heat the surrounding air to temperatures five times hotter than the surface of the sun.

4) The first graphical web browser, Mosaic, was released in 1993 and played a key role in popularizing the World Wide Web.