Cryptocurrencies have become increasingly popular in recent years, and the market is flooded with thousands of digital coins. However, there are only a few cryptocurrencies that are considered the "basis" of the industry. These cryptocurrencies are widely accepted and have established themselves as the foundation of the crypto world.

Bitcoin is the most well-known and widely used cryptocurrency. It was created in 2009 by an anonymous person or group using the pseudonym Satoshi Nakamoto. Bitcoin operates on a decentralized network, which means it is not controlled by any central authority. Transactions are recorded on a public ledger called the blockchain, and the security of the network is maintained by a process called mining.

Ethereum is the second most popular cryptocurrency, and it is often seen as the platform that has brought about the rise of decentralized applications (dApps). Unlike Bitcoin, Ethereum is not just a currency; it is a blockchain-based platform that allows developers to create dApps and smart contracts. The platform has its own cryptocurrency called Ether, which is used to pay for transaction fees and services within the network.

Litecoin is a cryptocurrency that was created in 2011 by Charlie Lee, a former Google engineer. It was designed to be a "lite" version of Bitcoin, with faster transaction speeds and lower fees. Litecoin uses a different mining algorithm than Bitcoin, which makes it easier to mine using consumer-grade hardware.

Ripple, also known as XRP, is a cryptocurrency that was created by Ripple Labs in 2012. Unlike Bitcoin and Ethereum, Ripple is not based on a decentralized network. Instead, it is a centralized digital currency that is used to facilitate cross-border payments. Ripple's goal is to provide a faster, cheaper, and more reliable alternative to traditional payment methods.

In conclusion, these four cryptocurrencies - Bitcoin, Ethereum, Litecoin, and Ripple - are considered the basis of the crypto industry. While there are many other digital coins available, these four have established themselves as the most widely used and recognized cryptocurrencies in the world. They have paved the way for the development of new blockchain-based technologies and applications, and their influence is likely to continue to grow in the years to come.