Blockchain Academy
We'll get together for networking with people interested in Blockchain including developers and anyone curious about Blockchain.

Decentralization

Decentralization is the core value of blockchain. The data has been maintained by the central server in the traditional network system, whereas it is done by the network users in the blockchain.

(Image source : https://www.bitdegree.org/tutorials/centralized-vs-decentralized/)

As the image shows, in centralized network, the hackers or malicious administrators can target only the central point to exploit the personal information and the data; however, it is harder for them to attack the decentralized network, where they have to manipulate every single data in every single node. In the decentralized system, a consensus mechanism is essential because all the nodes need to share the same data and decide which data is authentic. Depending on the type of method, the consensus mechanism can be categorized as public and private blockchain; in public blockchain, everyone can write the data; in private blockchain, only trusted ones have authority to access the data which is not quite completely decentralized.

Not every distributed network is decentralized network.

The difference and the exact definitions of these two terms can be found in the post "The Meaning of Decentralization" written by Vitalik Buterin known as a founder of Ethereum. Instead of a central point to make decisions, all the participated nodes make decisions on data together in the decentralized network. Vitalik said on the post, "Blockchains are politically decentralized (no one controls them) and architecturally decentralized (no infrastructural central point of failure) but they are logically centralized (there is one commonly agreed state and the system behaves like a single computer)".

(Image source : HTTPS://MEDIUM.COM/@VITALIKBUTERIN/THE-MEANING-OF-DECENTRALIZATION-A0C92B76A274)