Read this whitepaper: "Bitcoin: A peer-to-peer Electronic Cash System" by Satoshi Nakamoto. It is the first paper on the topic (although it didn't use the word "Blockchain").
Simplest definition: blockchain is a decentralized database.
You can visit the following source in order to understand Blockchain.
To understand basic:
https://en.wikipedia.org/wiki/Blockchain
https://www.springer.com/la/book/9781484234433
For research purpose:
K. Christidis and M. Devetsikiotis, "Blockchains and Smart Contracts for the Internet of Things," in IEEE Access, vol. 4, pp. 2292-2303, 2016.
M. D. Pierro, "What Is the Blockchain?," in Computing in Science & Engineering, vol. 19, no. 5, pp. 92-95, 2017.
Xu Wang, Xuan Zha, Wei Ni, Ren Ping Liu, Y. Jay Guo, Xinxin Niu, Kangfeng Zheng, "Survey on blockchain for Internet of Things", Computer Communications, Volume, 136, 2019, Pages 10-29.
Fran Casino, Thomas K. Dasaklis, Constantinos Patsakis, "A systematic literature review of blockchain-based applications: Current status, classification and open issues", Telematics and Informatics, Volume 36, 2019, Pages 55-81.
Interesting question! You can read our article https://www.researchgate.net/publication/327690411_From_Hype_to_Reality_A_Taxonomy_of_Blockchain_Applications
The blockchain Technology is used to ensure the big data that caused increasingly.
It works as a chain of blocks contains the transaction ( data) , each pair of blocks contain encryption key to ensure the security data in both of them. It has set of advantages that divide these big data into set of blocks that decrease the bandwidth and increase the transmission data in more secure way.
It is used in set of applications especially that contains private data like hospital, bank and others
Bloclchain is a distributed electronic record that is shared between all members and its content is kept identical between different members and update simultaneously. It has two major advantages 1- provides security and privacy with help of advanced cryptographic tools 2- Provides Distributed Autonomous functionalities with help of smart contract. Please see this reference for more information:
A Blockchain Enabled Cyber-Physical System Architecture for Industry 4.0 Manufacturing Systems
Please read the following paper : Ferrag, M. A., Derdour, M., Mukherjee, M., Derhab, A., Maglaras, L., & Janicke, H. (2019). Blockchain technologies for the internet of things: Research issues and challenges. IEEE Internet of Things Journal, 6(2), 2188-2204. https://ieeexplore.ieee.org/abstract/document/8543246/