What are some examples of common knowledge?

Common knowledge includes facts that are widely accepted and easily verifiable, such as the Earth orbits the Sun, water freezes at 0 degrees Celsius, and that there are seven continents. Historical events like World War II occurred from 1939 to 1945, and general cultural references, like Shakespeare being a famous playwright, also fall into this category. Additionally, basic scientific principles, such as gravity causing objects to fall, are considered common knowledge.