Market Capitalization is total market value of a company's equity. It is one of many ways to value a company and is calculated by multiplying the price of the stock by the number of shares issued. If a firm has one type of stock its market capitalization will be the current market share price multiplied by the number of shares. However, if a company has multiple types of equities then the market cap will be the total of the market caps of the different types of shares. In most publications or references market cap is broken down into the mega cap, large cap, mid cap, small cap, micro cap, and nano cap. Market Cap is a measurement of business as total market value of all of outstanding shares at a given time, and can be used to compare different companies based on their size.