Market cap stands for "market capitalization" refers to the total value of an asset (whether it's a currency or a company). You can also think of it as the total amount of money in an asset at one time.

For companies, you get the total market cap by multiplying the stock price by the total number of stocks.

For a cryptocurrency, you get the total market cap by multiplying the current price by the total supply. For example, if bitcoin is worth $10,000 and its total supply is 18,000,000, then the total market cap is $180,000,000,000 ($10,000 x 18,000,000), or $180 billion if you got dizzy from counting zeros.

You can get the market cap of the entire crypto market by adding together all the individual market caps of each cryptocurrency.

People often speculate on the future price of an asset by evaluating its market cap to what they think it could be in the future. For example, if someone believes that bitcoin could reach $1 trillion dollars one day (approximately the value of Apple), and there's a maximum supply of 21 mllion bitcoin, they would speculate that the future price of bitcoin would reach $47,619 ($1 trillion / 21 million).