Litecoin

Litecoin (LTC) was released on October 7, 2011. It is currently the altcoin with the highest market value, approximately 2% of the market value of BTC. The current unit price is US$2.31, with a total currency value of US$38 million.

This is also a distributed (decentralized) digital currency. Unlike the SHA256 mining algorithm used by Bitcoin, LTC uses the scrypt algorithm. The unique algorithm is also the key to stand out from the altcoins. The scrypt algorithm uses SHA256 as its subroutine, and scrypt itself requires a lot of memory. Each hash is used as an input seed, and then requires a lot of memory to store another seed. Pseudo-random sequence, the hash value is output based on the pseudo-random point of the generated sequence. In the mining of BTC (Bitcoin), it is no longer enough to rely on simple graphics card mining (it takes about ten to dozens of days to mine a BTC with a general configuration graphics card). The emergence of various expensive mining machines has improved the ability of ordinary people to mine through mining. The threshold for miners to obtain BTC, and LTC has certain advantages in using PC graphics cards for mining. (This paragraph comes from Zhihu.)

Litecoin has made some technical improvements compared to BTC. If BTC is gold now, then LTC is silver for the time being.

The biggest advantage of Litecoin is that it can confirm authenticity faster. The virtual currency is designed and maintained by Charles Lee. Bitcoin transactions require verification, and the average verification time is more than 10 minutes. Most trading websites require 1 hour for verification. Litecoin transaction confirmations take an average of 2.5 minutes, and developers claim that shortening verification increases the utility of the virtual currency. Bitcoin mining is most efficient with custom machines and AMD GPUs, making it almost unprofitable for miners using CPU mining. Litecoin mining excludes GPUs and custom processors, so it is not overly reliant on a small number of professional miners.

PPCoin

PPCoin (PPC) was released on August 19, 2012, and has improved on the original technology of BTC. Use proof-of-stake and add the concept of coin age.

PPCoin is a fork project of Bitcoin that aims to achieve energy efficiency and maintain the best performance of the original Bitcoin as much as possible. The unit price of PPCoin is US$0.22, with a total currency value of US$4 million.

PPCoin does not have a fixed money supply upper limit, but this does not mean that PPCoin has significant inflation than Bitcoin. Bitcoin can be compared to gold. The annual inflation of gold is about 1-3%. Although gold does not have a known upper limit on the money supply, we still know that it is a reliable scarcity.

There are two types of minting of PPCoin, proof of work and proof of stake. The minting rate of proof of work is affected by Moore's Law, which depends on the exponential growth of our proof of work power. What everyone knows is that Moore's Law will eventually end, and by then the inflationary PPCoin may have approached the level of gold. Proof-of-stake minting, on the other hand, has a maximum inflation rate of 1% per year. At the same time, PPCoin transaction fees are burned to combat inflation. So overall, PPCoin’s coinage design is still a very low inflation design in the future, which can be comparable to Bitcoin.

PPCoin’s reward method is similar to a lottery, and the odds of winning are determined based on the number of PPCoin held by miners. Sunny King, one of the founders, said that their design is based on the new concept of long-term energy efficiency.

Terracoin

Terracoin (TRC) was released on October 26, 2012, with a total currency volume of 42 million. The speed per block is 2 minutes, which is slightly faster than LTC. There is nothing technically special, similar to the fact that BTC production is halved every 4 years.

However, the operation team seems to have a strong business background and may be better than other Bitcoins in circulation. The development of virtual currency is receiving more and more attention. Now some teams with business backgrounds have entered, which will accelerate the development of virtual currency.

Namecoin

Namecoin is a distributed domain name system based on Bitcoin technology. Its principle is the same as Bitcoin. This open source software was first released on April 18, 2011.

Namecoin is generated from an origin block different from Bitcoin’s main transaction block, using a new blockchain (blockchain), independent of Bitcoin’s blockchain, because it is based on Bitcoin and domain names. Security, distribution, robustness, encryption, and migration are all mathematically guaranteed. You can mine Namecoin at the same time as you mine Bitcoin.