A blockchain is the process of storing data by encrypting the encrypted information of all the financial or asset transactions that are taking place around the world in a fairly specific period of time. In this system, a distributed and decentralized laser is completely immutable with that block. It is actually a little difficult to understand in one sentence. That's why I try to say a little broken. The blockchain I'm talking about in my writing is the bitcoin blockchain. There are so many types it's hard to say.
Inside each block is all the data on the number of transactions in the world in the last 10 minutes or so. This data is open but encrypted, meaning everyone can see it, but if you want to read it, you need a private key. What people will see is the amount of transactions. It is not possible to know in this way whose money has gone to whom. The following picture shows what a transaction looks like.
Every block in the blockchain is completely immutable. Once a block is added to the chain, it is impossible to change it.
The blocks sit side by side in the order of their creation. Each block knows which block is before it. Thus one block is connected to another.
Blockchain is a distributed and decentralized system, meaning it has carbon copies on thousands of servers around the world. So even if one or a hundred servers or computers go down, nothing will happen to the blockchain.
Cryptocurrency
Cryptocurrency, like our conventional currency, is a type of currency. This cryptocurrency is used for transactions through blockchain. There are many such currencies, such as Bitcoin, BitCash, Monero, Lightcoin, etc. Bitcoin is currently the most well-known and popular cryptocurrency. The price of this virtual currency seems to have gained rocket speed.
Protection from hacking
As I said before, the biggest feature of blockchain is that adding a block to a blockchain means that the block is completely unchangeable. No change in the block is possible in any way. That means hacking is fairly impossible. Why impossible? The reason is funny. First, there are many transaction records within a block. These are all encrypted data. In other words, it is impossible to read the data inside a transaction without a private key. Suppose a well-known hacker has made this impossible possible. Suppose a hacker cracks the block number 10,000 and changes a transaction record as needed. What happens now? As we already know, each block has a hash of its previous block. This combines the previous hash, the transaction data of the block and the nonce but creates the SHA256 hash of that block. So there will be a huge problem. The problem is, the SHA256 hash of the block will change as soon as the hacker gets inside the 10,000th block. Changing the hash means that the block became invalid immediately. Since the hash of this block was in 10001 block before hacking, 10001 is now invalidated due to the new hash in 10000 block. When 10001 is lost, then 10002 is lost immediately. In this way, like chain reaction, all the blocks from 10,000 blocks up to this moment will be invalidated if not destroyed. The block (up to block 499982 at the moment) needs to be re-mined or hashed correctly and each block has to be verified with about 52% miner. Now we know from the previous information, the problem here is in the hands of hackers The time is approximately 10 minutes, that is, the time between adding a new block. Where one block can be mined in 10 minutes, it would not be wrong to say that it is impossible to mine so many blocks at this time.
Blockchain has been a great revolution and its the heart of cryptos