What is the m?

"M" can refer to many things depending on the context. Here are some possible meanings:

• In English, "m" is the 13th letter of the alphabet.
• "M" is the Roman numeral for 1,000.
• "M" is a common abbreviation for "million."
• "M" is the chemical symbol for the element molybdenum.
• The "M" rating in video games indicates that the game is intended for mature audiences.
• "M" is the first initial of the word "mass" in Einstein's famous equation E=mc², which describes the relationship between energy, mass, and the speed of light.
• In the film industry, "M" can refer to the ratings system used in some countries, such as PG-13 for movies suitable for viewers aged 13 and over.
• "M" is a measure of distance in astronomy, where it stands for "magnitude" and indicates the brightness of stars and other celestial objects.
• "M" is the title of a 1931 German film directed by Fritz Lang, which is considered a classic of the thriller genre.
• "M" is also a common abbreviation for the word "millionaire."