What is blockchain technology?

[Casey]

How does blockchain technology work, and why is it considered very secure for cryptocurrencies?

[Kaile]

Blockchain technology is like a digital database where everyone can see the same information but can't change or manipulate the data. 
Data is stored in the form of blocks, so any new data that is added is added in the form of blocks, which makes it the most secure option. These blocks are linked together and form a chain. For this reason, we refer to it as a blockchain.

Its transparency, decentralized features, and data are present in encrypted form, making it a more secure option for cryptocurrency.

If you want to know more you can check out this page also: https://www.investopedia.com/terms/b/blockchain.asp

[Scarlett]

You are saying blockchain technology is the most secure option for cryptocurrency, but if the mining is mostly controlled by a few big players, then how can the blockchain network stay fair and independent?

[Jamie]

For managing a large number of transactions with efficient transaction processing, what kind of challenges will blockchain technology face?

[Casey]

Thanks for the reply @Kaile , but I am still confused about how this blockchain technology prevents me from data tampering and unauthorized access and ensures us immutable records.