There are many articles that can be searched about the meaning of “Block Chain”, but the problem is that almost all articles are explained in languages ​​that are very difficult to understand. In addition, there are only many letters that are very long in length. I was also the person who faced that problem during the first study of this technology and when there was clear knowledge, even though it didn’t go into much detail. But it can be transferred to other people for further study. That’s the origin of this article. I will explain in detail and as easily as possible.

The meaning of the block chain.

Blockchain is storing information by dividing data into blocks or boxes. Then kept united, each block will have a chain or chain that is bound together to be used in checking the validity between blocks Together, together calling “Block Chain”
What information is contained in each block?

Then what does each function do

After understanding the big picture of the blockchain, we go into detail, look at it in each block. What’s saved? How does it work Why is it safe and widely accepted quickly?


The information here is a list of financial items that have occurred. (Transaction) Each block can hold more than hundreds of these items. For example, Alice transfers Bob to 100 $, which is considered Transaction 1. If transferred 10 one time, it will maintain 10 Transactions.

Hash – Hash

Hash Transactions:

Is the number generated by the system for each transaction that occurs To check the accuracy of each item Is a value that is never repeated consisting of numbers and letters that are very long Do not remember, if the brain is not divine enough

An example

Alice transferring Bob to money = 100 $ will make a set of Hash 1
If Alice transfers money to Bob again, regardless of the amount, a new hash will be created. Can’t use the real one Even if it’s the same person, transferring each other

Hashes from the previous block:

Apart from the hash created for each program, as mentioned at the beginning there are other hashes between the blocks. Set 1 is made to be used to check between blocks.

An example

The first block stores information transfers until the information is almost full. But before it is full, the hash is made to cover the end of the block and will be sent to the next block. After the next block receives a hash, it will be saved as a connector to the previous block. And it goes on like this every block


If someone tries to steal or change information on the block, for example, replacing block 100 with 50 will be very difficult. Because you have to correct the hash that will be properly connected to each other if you switch between blunt placement and can’t connect with each other

Because the structure is designed like this Make items on the blockchain unable to return to edit or delete
Want to know what Hash looks like? Click here After entering the website, try to fill in any information. Hashes will be made soon.

Want to know if hash is used between blocks How does it look? Click here Then try to fill out information to play too

What makes a safe chain block, high horse, ….

Collect all blockchain data Not stored in one place like the original database system. But it will spread all the same data to connected computers all over the world … (Repeat it all over the world). Such systems are called “peer to peer networks” Computers that are connected together are called Nodes.

When certain transactions occur in the system Take the same example. Alice transfers Bob to the money. Data will be distributed to all connected computers first. Regardless of how many thousands of devices are connected, it will gradually spread until there is the same data set.

When receiving information that Alice transfers money to Bob, Node also has another role: Check to see if the program is correct, the application will use the hash recorded to check When all the machines in the system verify and confirm that the information is correct, then only save the data to the block

This is the main strength of blockchain technology. Because it’s very difficult to penetrate or almost impossible … if you still can’t think how difficult it is

Let’s imagine the situation that we are a hacker … by chance you can hack the banking system in one place … After you have hacked, you can transfer money, add money, or do whatever you can to give us money. More is possible because bank information is stored and managed by the bank itself. But if you can hack the key chain even if you can get into one machine then you can’t do anything because the data on other nodes is not the same as what we edited. How is it possible to hack all computers in this system?

Another brief summary about blockchain

Blockchain is a new storage method. By dividing data into square blocks and having a chain connecting each block
Use hashes to confirm the accuracy and security of each transaction and the hash will never be duplicated.
Distribute information and save it on each node that is connected to the system.
Nodes that are connected to the system besides collecting blockchain data will also be responsible for confirming transactions that occur on the network. If there are items that have nodes that do not match, it will be considered invalid.

Hopefully all the content about the blockchain in this article will be useful for those who seek knowledge in this field. If you read and like it, then suggest friends or share this article. This only encourages to find more knowledge.

This article has been translated and rewritten from the original: Hackermoon Can be distributed But must put the reference link back every time

Saravana N S

He has a demonstrated history of working in the information technology and services industry. He likes to discuss software testing, big data, and latest digital trends. Apart from work, he enjoys watching movies, listening to music and clicking pictures with his DSLR.

Write A Comment