After their transition from wood to plastic in the late 1940's, Lego began to use pneumatic injection molding machines to make its pieces. In 2004 Danish
mathematics professor, Søren Ejlers calculated that the number of unique ways you can combine six 2×4 LEGO bricks of the same colour is 915,103,765. Today the company
has over 7,000 individual molds, creating truly endless possibilities for building.
When the company began, their users were limited to just 7 colors (white, gray, black, red, blue, yellow, and occasionally green). Their palette has expanded
over time and now features 65 colors. An updated chart is shown below.
