Bitcoin ist so etwas wie die Mutter aller Kryptowährungen. Sie gibt es mittlerweile seit ca. neun Jahren und interessanterweise weiß man bis heute nicht, wer ihr eigentlicher Gründer ist. Das hat der Nachfrage aber nicht geschadet. Zum Ende des Jahres 2017 sah es sogar kurz danach aus, als würde er die 17500 € Grenze knacken. Leider hat das nicht geklappt und im April 2018 liegt der Kurs bei ca. 5000€.
Litecoin: Litecoin is probably the second most important digital coin [true in 2015, it is still relevant today]. It had the third-highest market cap as of June 2015, but today it sits closer to 7. Despite the decline, CPU mining is still sort of possible, people know what a Litecoin is, it uses essentially the same technology of Bitcoin, and it costs about 1/50th – 1/100th of what Bitcoin does (depending on the day). A Litecoin is a lot like a Bitcoin before the whole ‘Silk Road‘ controversy, or as some people would say “a Litecoin is like a Bitcoin except with a value closer to what a reasonable person would expect a digital coin to have in a rational market.”
A cryptocurrency is a digital or virtual currency designed to work as a medium of exchange. It uses cryptography to secure and verify transactions as well as to control the creation of new units of a particular cryptocurrency. Essentially, cryptocurrencies are limited entries in a database that no one can change unless specific conditions are fulfilled.

Founded in 2011, Kraken is the largest Bitcoin exchange in euro volume and liquidity and is a partner in the first cryptocurrency bank. Kraken lets you buy and sell bitcoins and trade between bitcoins and euros, US Dollars, Canadian Dollars, British Pounds and Japanese Yen. It’s also possible to trade digital currencies other than Bitcoin like Ethereum, Monero, Ethereum Classic, Augur REP tokens, ICONOMI, Zcash, Litecoin, Dogecoin, Ripple and Stellar/Lumens. For more experienced users, Kraken offers margin trading and a host of other trading features. Kraken is a great choice for more experienced traders. Check out the Kraken FAQ

Purchasing and mining cryptocurrency has evolved rapidly in recent years, and many options have captured worldwide attention. Users like the idea of cutting out third parties, such as governments and banks, and instead dealing with peers directly. For example, if a bank or company such as PayPal decided for some reason that your account had been misused, in an instant, your assets could be frozen without consulting you.
Note: In most cases, you’ll have a hard time trading anything other than Bitcoin, Litecoin, Bitcoin Cash, and Ethereum for actual fiat (fiat being the centrally issued money of nations). You can trade most coins at online cryptocurrency exchanges, and you can use some coins to buy certain things online, but converting an altcoin into fiat currency means converting to a major coin first (BTC or ETH generally). A coin having a theoretical value in USD doesn’t mean that anyone is going to give you USD or pay that rate for your coins. This is more like selling penny stocks or trading one baseball card for another than actually having money on hand. So, keep that and the volatility of the markets and coins in mind when investing.
Pundi X originates in Indonesia, and while cryptocurrency exchanges are permitted, cryptocurrency payments for goods and services are currently banned by the government. Pundi X is able to deploy their hardware without breaking the law because their POS system defaults to accepting payments from non-cryptocurrency systems, like bank cards and Apple Pay.
Zcash, a decentralized and open-source cryptocurrency launched in the latter part of 2016, looks promising. “If bitcoin is like http for money, zcash is https," is one analogy zcash uses to define itself. Zcash offers privacy and selective transparency of transactions. Thus, like https, zcash claims to provide extra security or privacy where all transactions are recorded and published on a blockchain, but details such as the sender, recipient, and amount remain private. Zcash offers its users the choice of “shielded” transactions, which allow for content to be encrypted using advanced cryptographic technique or zero-knowledge proof construction called a zk-SNARK developed by its team. As of February 9, 2019, Zcash had a market cap of $291.25 million and a value per token of $49.84.
The term altcoin has various similar definitions. Stephanie Yang of The Wall Street Journal defined altcoins as "alternative digital currencies,"[20] while Paul Vigna, also of The Wall Street Journal, described altcoins as alternative versions of bitcoin.[21] Aaron Hankins of the MarketWatch refers to any cryptocurrencies other than bitcoin as altcoins.[22]