Market Capitalization is the “market value” of a company. This is often referred to as a company’s “Market Cap”. These terms mean the same thing. The “market value” of a company is the “share price” times the total number of “shares”. Large companies, “sometimes small” are divided up into shares. This allows more than one investor to buy a part of the company. A company’s “Market Cap” goes up and down a lot depending on many different things such as how much money the company profits as well as how the stock market view the future outlook of the company.
The company with the second biggest “Market Cap” in the world is Apple. (Between 300 and 400 Billion USD)
Facebook’s “Market Cap” is around 50 Billion USD to give you an idea.