Decentralization

Means to spread a business or operation across multiple locations. You then move power and capital from central areas and distribute it over a larger area both geographically and socially.

In the field of cryptocurrency and "blockchain networks", decentralized means that the users isn't dependent on a central control unit to perform a task in the network. The network thus works in contrast to large organizations like banks and authorities. In a "blockchain network" you do not have to trust a spesific user or entity, all members of the network have access to the same data in the form of an official "transaction book" also called a ledger. If a user in the network tries to change something that is in the transaction book, the attempt to change and manipulation of the network will be rejected by the majority of the members. A decentralized network are therefore stronger, safer and more stable if there are more users/computers part of the network, and how many computers the transaction book is spread on.

A "blockchain network" also does not depend on a central database that stores the information in the network. Thats's because all computers in the network have access to the same data/transaction book, and can with the official book update their local book accordingly when transactions take place in the network. Since all users have access to the same information, a decentralized "blockchain network" is more robust than a centralized network. "Blockchain networks" also have protection against attacks and loss of power supply, as the computers/users in the network are spread all over the globe. You also get a network that is always on and in most cases always working, which means that you do not have to be afraid that transactions in the network won't be performed.