Blockchain technology is an open-source chain that gives room for everyone to air their views (decentralization) having a collective agreement in an organization could be somewhat complicated my opinion could differ from others.
Unlike centralization where autonomous decisions could be made by one person, in an open-source space like blockchain, it's way different as collective decisions are made base on votes or any related unbiased methods.
What happens in such situations when there seem to be individual differences among a collective group of people?
Fork in blockchain technology is a logical means introduced by the chain developers to tackle such challenges among users.
What is a fork in the blockchain technology
A fork happens when a single blockchain diverges/split into two separate paths and still maintain the same rule of communication and protocol without altering the block paths like means of transactions, although speed and scalability can differ as processing bytes can differ.
A fork can also occur when two or more miners find a block at the same time making two or more blocks have the same height (accidental fork).
Blockchain fork is generally a split in the blockchain network since it's open-source that allows improvement to be made and the code is freely available which allows anyone to introduce newly proposed improvements that will make the blockchain more scalable and user-friendly.
Forks are often associated with the creation of new cryptocurrencies like the case of bitcoin where developers proposed block size should be increased although some were not convinced with such idea of increasing block size this lead to a split of having bitcoin cash which was forked out of bitcoin.
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Bitcoin (BTC) split fork lead to the creation of bitcoin cash (BCH)
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Another typical example of the fork was steem a social decentralized proof of stake (DPoS) platform that leads to the existence of hive
Reasons for a fork in the blockchain
Settling difference; in most cases to resolve conflict among miners, developers, and node validators a fork will be implemented which will lead to the spit of new currency in the blockchain network.
Add new functionality; to fork means to improve or upgrade a particular blockchain which will correct important security found in the old blockchain improve the block transaction speed.
Final thought
Implementation of a fork in the blockchain technology was a very good means of resolving complicated issues in the crypto space being open source makes it even easier for users to chip in ideas that will improve the blockchain functionality and make it more secure against external threats.