Litecoin (from English lite - "easy", English coin - "coin") - fork Bitcoin, a peer-to-peer electronic payment system using the same crypto currency.
Litecoin is the second after Namecoin fork Bitcoin and has only slight differences from it. As of July 10, 2018, 1 LTC is equivalent to 78.00 USD according to CoinMarketCap data and was the sixth largest total value of crypto currency.
Litecoin can be used for exchange on Bitcoin or common money in exchangers, as well as for electronic payment for goods or services from sellers ready to accept them.
To ensure the functioning and protection of the system, cryptographic methods are used.
In May 2017, SegWit support was activated in the Litecoin software .
Comparison of Bitcoin and Litecoin
In Bitcoin and Litecoin networks, the data is recorded in the same way - as a linked chain of blocks, each of which contains a hash of the previous one. The difference is only in the function of finding the hash in the chains (for Litecoin - scrypt, for Bitcoin - SHA-256), for the average time of the block finding by the network and the methods of confirming the performance of the work (see Mining section).
In the Litecoin network, as in other crypto-currencies, transactions indicate the transfer of a certain amount of crypto currency from one address to another. Litecoin-address is formed on the basis of a public key using SHA-256 hashing. Litecoin addresses consist of 33 characters and start with the letter L or the number 3.
After the addition of SegWit support to Litecoin in April 2017, the addresses starting with M. began to correspond to the addresses for 3. With the help of a special converter it is possible to mutually convert the addresses of these two formats.
To support the network and ensure the required level of security (in particular, to prevent the possibility of attack "Double Spending"), the mechanism of cyclic hashing is used. In case the numerical value of the hash of the header of the block is equal to or lower than the parameter generated by the system, the condition is considered fulfilled and a new block is created. Otherwise, the block of random information in the header is changed and the hash is recalculated. When a variant is found, the node sends the received block to other connected nodes. Other nodes check the block. If there are no errors, then the block is considered added to the chain and the next block must include its hash.
The result of hashing is almost unpredictable. Thus, the probability of creating a new block for each individual user is equal to the ratio of the number of hashes per second (usually expressed in KH / s), calculated on its equipment, to the number of calculated hashes per second in the entire network. The one who created the new block receives a reward from some new coins. The process of searching for a suitable hash to form a new block is called mining.
For finding a new block in the network, a reward is set, initially equal to 50 LTC and decreasing by half for every 840,000 units.
Bitcoin uses the SHA256 hash function to prove its performance, which makes Bitcoin mining an extremely parallel task. Litecoin uses scrypt as evidence of performance. The scrypt hash function uses the SHA256 as a subroutine, relying on a large number of arithmetic computations, but also requiring quick access to large amounts of memory. This makes launching multiple instances of scrypt on the ALU of a modern graphics card somewhat more difficult. This also means that the cost of manufacturing specialized equipment for mining on ASICs or on FPGAs will be significantly higher than the cost of manufacturing similar devices for SHA256    .
Since modern GPUs have large memory capacities, they are more suitable for Litecoin mining, but their advantage over the CPU is less significant than in the case of Bitcoin (10 times the advantage compared to 20 for Bitcoin) .
The parameters of the scrypt function used by Litecoin (N = 1024, p = 1, r = 1) allow non-latent Litecoin users to run the client in multitasking mode, without affecting system performance. These parameters, according to Colin Percival, the creator of scrypt, also reduce the efficiency of using ASIC approximately 10 times  .
Since the probability of creating a new block and receiving a reward depends on the computing power of the user equipment, then with the increase in the number of miners and their total productivity for the average user, the chance is very low. To increase the probability of receiving awards, the miners combine their computing power into groups. If successful, the award is distributed among the participants.
The speed of the transaction
The complexity of calculating Litecoin is selected in such a way that, on average, one block is generated 2.5 minutes, which is 4 times faster than Bitcoin, this allows you to receive transaction confirmation more quickly.  
Transaction, as a rule, is considered completed after 6 blocks, or 15 minutes.
The transaction speed increased significantly after SegWit was activated in the lightbox network .