A blockchain is a distributed, decentralized database that exploits the peer-to-peer technology and that is usable from anyone on the net. In other words, it is a ledger that keeps the history all of the cryptocurrency transactions from its conception. In order for a transaction to happen, the nodes within the 50% + 1 of blockchains must approve the operation. It is an open source system that does not middlemen like banks to function and to make transactions. Transactions are distributed on nodes that validate them and insert them in the first available block. A decentralized, ungoverned system, that uses time stamps to check and prevent if the same quantity of cryptocurrency is used to make more than once transaction. Through the blockchain, you can now also publish all applications that, for privacy or security reasons, are stored on private and proprietary servers.
Each node of the blockchain can contain a fixed amount of cryptocurrency, which is released from the miner, devices with a strong hashing power that solve mathematical operations that protect the transaction. This process self-regulates to release a node within a defined timeframe. Therefore, the more hashing power is used to process the mathematical formulas, the more complex the algorithms become. Whoever clears a node receives a defined amount of cryptocurrency. Clearing nodes of the blockchain leads to an income based on the number of transactions within the blockchain itself.
Why does it work? Because all within the blockchain gain profit.
If taken as is, the blockchain can be used in all kinds of technological fields in which there is a relation between individuals. It guarantees trading of shares, titles and goodness of a certain operation, can replace notary deeds, and validate voting systems. This is because each operation is overseen by nodes of the networks that validate or reject the operation and that maintain anonymity.