More than 6,700 different cryptocurrencies are traded publicly, according to CoinMarketCap.com, a market research website. And cryptocurrencies continue to proliferate, raising money through initial coin offerings, or ICOs.

The total value of all cryptocurrencies on Feb. 18, 2021, was more than $1.6 trillion, according to CoinMarketCap, and the total value of all bitcoins, the most popular digital currency, was pegged at about $969.6billion.

Starting with 2022 the prices have gone down and the industry is experiencing a "crypto winter".

Crypto projects come and go. However you can think of crypto projects in 2 buckets:

• Bitcoin: the OG value-storing coin. It's the new digital gold.
• Programable blockhains: where Ethereum rules. And where most competition lies with projects like Solana, Polkadot or Cardano. 

Some of the reasons:

• Some see cryptocurrencies such as Bitcoin as the currency of the future and are racing to buy them now, presumably before they become more valuable
• Some like the fact that cryptocurrency removes central banks from managing the money supply since over time these banks tend to reduce the value of money via inflation
• Some like the technology behind cryptocurrencies, the blockchain, because it’s a decentralized processing and recording system and can be more secure than traditional payment systems
• If price in $ goes up it may hurt long-term acceptance as a new way to move money

Cryptocurrencies may go up in value, but many investors see them as mere speculations, not real investments. The reason? Just like real currencies, cryptocurrencies generate no cash flow, so for you to profit, someone has to pay more for the currency than you did.

Cryptocurrency needs stability and Bitcoins price volatility creates a conundrum.

If bitcoins might be worth a lot more in the future, people are less likely to spend and circulate them today, making them less viable as a currency. Why spend a bitcoin when it could be worth three times the value next year?

While some cryptocurrencies, including Bitcoin, are available for purchase with U.S. dollars, others require that you pay with bitcoins or another cryptocurrency.

To buy cryptocurrencies, you’ll need a “wallet,” an online app that can hold your currency. Generally, you create an account on an exchange, and then you can transfer real money to buy cryptocurrencies such as Bitcoin or Ethereum.

There’s no question that they’re legal in the United States, though China has essentially banned their use, and ultimately whether they’re legal depends on each individual country.

Cryptocurrency is an incredibly speculative and volatile buy. Stock trading of established companies is generally less risky than investing in cryptocurrencies such as Bitcoin.