Litecoin
Litecoin (LTC) was issued on 20110.07, which is the counterfeit currency with the highest market value at present, accounting for about 2% of BTC's market value. At present, the unit price is 23 1 USD, and the total monetary value is 38 million USD.
This is also a distributed (decentralized) digital currency. Different from SHA256 mining algorithm used by Bitcoin, LTC uses scrypt algorithm. Unique algorithm is also the key to stand out from counterfeit money. The scrypt algorithm uses SHA256 as a subroutine, but scrypt itself needs a lot of memory, and each hash is used as the input seed. Then, together with another pseudo-random sequence that needs a lot of memory, the pseudo-random point of the sequence is generated and the hash value is output. In the mining of BTC (Bitcoin), it is not enough to rely on a simple graphics card to mine (with the general configuration of graphics cards, it takes about ten to dozens of days to dig a BTC). The emergence of various expensive mining machines has raised the threshold for ordinary people to obtain BTC through mining. LTC has certain advantages in mining with PC graphics cards. (This passage is from Zhihu. )
Litecoin has made a little technical improvement compared with BTC. If BTC is gold now, then LTC is silver for the time being.
The biggest advantage of Litecoin is that it can confirm the authenticity more quickly. This virtual currency was designed and maintained by Charles Lee. Bitcoin transactions need to be verified. The average verification time exceeds 10 minute, and most trading websites need 1 hour. Litecoin transaction confirmation takes an average of 2.5 minutes, and developers claim that shortening verification increases the practicality of virtual currency. Custom machine and AMD GPU have the highest bitcoin mining efficiency, making it almost unprofitable for miners who use CPU to mine. Litecoin's mining excludes GPU and custom processor, so it doesn't rely much on a few professional miners.
PPCoin
PPCoin(PPC) was released on August 20 12 and 19, which improved the original technology of BTC. Use the stack to verify and add the concept of coin age.
PPCoin is a fork project of Bitcoin, with the goal of achieving energy efficiency and maintaining the best performance of the original Bitcoin as much as possible. The unit price of PPCoin is $0.22, and the total currency is $4 million.
There is no fixed upper limit of money supply for PPCoin, but this does not mean that PPCoin has obvious inflation than Bitcoin. Bitcoin can be compared to gold. The annual inflation rate of gold is about 1-3%. Although gold has no known upper limit of money supply, we still know that it is a reliable and scarce product.
There are two kinds of PPCoin casting, work certificate and equity certificate. The coinage rate of work proof is influenced by Moore's law and depends on the multiplication of our work proof ability. As we all know, Moore's Law will come to an end. By then, inflation PPCoin may be close to the gold level. The most inflation rate of equity certificate casting is 1% every year. At the same time, it destroyed the transaction cost of PPCoin to fight inflation. Therefore, in general, PPCoin's coin design is still a very low inflation design in the future, which can reach the level equivalent to Bitcoin.
The reward method of PPCoin is similar to the lottery, and the winning probability will be determined according to 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.
Local currency
Terracoin(TRC) was put on sale on1October 26th, 2012 10, with a total currency of 42 million yuan. The speed of each block is 2 minutes, which is slightly faster than LTC. There are not many technical features, such as the production of BTC is halved every four years.
However, the operation team seems to have a strong business background, which may be better than other bitcoin in circulation. The development of virtual currency has attracted more and more attention. Now some teams with business background will enter, which will accelerate the development of virtual currency.
Named coin
Namecoin is a distributed domain name system based on bitcoin technology. Its principle is the same as bitcoin. The date of the first release of this open source software is 20 1 1 April, 2008 18.
Namecoin comes from an origin block different from the main transaction block of Bitcoin, and uses a new blockchain, which is independent of the blockchain of Bitcoin. Because it is based on bitcoin, the security, distribution, robustness, encryption and migration of domain names are mathematically guaranteed. You can dig bitcoin and Namecoin at the same time.
This project was put forward by bitdns discussion, mainly because it is dissatisfied with the defects of dns at present. The only top-level domain name of Namecoin is. Bit, and it costs Namecoin to register a. bit domain name.
In addition, what Q coins, Shanda coins, starting coins, and various online games coins are also virtual currencies.