Block chain services xmedia

 Blockchain is a cryptocurrency blockchain explorer service, as well as a cryptocurrency wallet and a cryptocurrency exchange supporting Bitcoin, Bitcoin Cash, and Ethereum. They also provide Bitcoin data charts, stats, and market information. A blockchain is a decentralized, distributed, and oftentimes public, digital ledger consisting of records called blocks that are used to record transactions across many computers so that any involved block cannot be altered retroactively, without the alteration of all subsequent blocks.

• Blockchain is a specific type of database.

• It differs from a typical database in the way it stores information; blockchains store data in blocks that are then chained together. 

• As new data comes in it is entered into a fresh block. Once the block is filled with data it is chained onto the previous block, which makes the data chained together in chronological order.

• Different types of information can be stored on a blockchain but the most common use so far has been as a ledger for transactions. 

• In Bitcoin’s case, blockchain is used in a decentralized way so that no single person or group has control—rather, all users collectively retain control.

• Decentralized blockchains are immutable, which means that the data entered is irreversible. For Bitcoin, this means that transactions are permanently recorded and viewable to anyone.

• For the purpose of understanding blockchain, it is instructive to view it in the context of how it has been implemented by Bitcoin. Like a database, Bitcoin needs a collection of computers to store its blockchain. For Bitcoin, this blockchain is just a specific type of database that stores every Bitcoin transaction ever made. In Bitcoin’s case, and unlike most databases, these computers are not all under one roof, and each computer or group of computers is operated by a unique individual or group of individuals.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               Blockchain technology accounts for the issues of security and trust in several ways. First, new blocks are always stored linearly and chronologically. That is, they are always added to the “end” of the blockchain. If you take a look at Bitcoin’s blockchain, you’ll see that each block has a position on the chain, called a “height.” As of November 2020, the block’s height had reached 656,197 blocks so far. 

After a block has been added to the end of the blockchain, it is very difficult to go back and alter the contents of the block unless the majority reached a consensus to do so. That’s because each block contains its own hash, along with the hash of the block before it, as well as the previously mentioned time stamp. Hash codes are created by a math function that turns digital information into a string of numbers and letters. If that information is edited in any way, the hash code changes as well.