So what the blockchain?
Blockchain (chain of blocks) is an immutable data structure consisting of a list of blocks where each next block contains a hash of the previous block. As a result of this hashing, the chain of blocks becomes unchanged: you can not change or delete a block from the middle of the chain without rebuilding all the blocks above, because the slightest change will require a rebuild (recalculating hashes) of all blocks above the changed one.
If the calculation of the hash of each block is computationally or economically complex operation, then the data change in the middle of the chain becomes practically impossible at all. The combination of the new block hash calculation complexity, as well as the ease of checking the correctness of the hash, provides blockchain with a serious resistance to unsanctioned changes. This is what holds the safety of bitcoin and other blockchains.
Thanks to this, blockchain projects can be publicly decentralized. That is, anyone can put the working node of the blockchain and generate new blocks. In most implementations of the blockchain for the generation of a block a reward is given – this process is called mining. And since it is difficult to mine, and your results can be easily verified, it is profitable to act only honestly. Otherwise, you will spend resources on mining, and other miners will not take your block – all the work is a nuisance. Thus, with complete decentralization and independence of individual nodes, the network of blockchain nodes operates as a single whole.
The IPDB a blockchain database network for the decentralized stack
IPDB is a ready-to-use public network with a focus on strong governance, all powered by BigchainDB.
Learn to securely share files on the blockchain with IPFS!
The most promising solution that’s available today is IPFS, or Interplanetary File System, created by the folks at Protocol Labs. It’s a peer-to-peer protocol where each node stores a collection of hashed files. A client who wants to retrieve any of those files enjoys access to a nice abstraction layer where it simply needs to call the hash of the file it wants. IPFS then combs through the nodes and supplies the client with the file.