According to Brian Behlendorf, the person who works to make blockchain technology a reality with Hyperledger, explained in an interview:
Blockchain is a digital ledger that records transactions or other data over time. But records in a blockchain can be made effectively indelible using cryptography, and a blockchain can be designed to be operated by a group of companies or individuals together such that no single entity controls the system or its data.
In a much simpler way, It offers a way for people who do not know or trust each other to create a record of who owns what, that will compel the assent of everyone concerned. It is a way of making and preserving truths.
Healthcare
The blockchain can be used to create a type of universal record with a timestamp, a library that enables data retrieval across diverse databases. This will become exceedingly valuable as precision medicine and the explosion of sensors, wearables and mHealth apps proceeds. The current health systems and the legacy health IT players quite simply are not well designed to manage the volume and types of data that are being generated today.
Finance
The most mature plans for using blockchains aim to cut costs for financial institutions in tasks such as settling transactions involving bonds or other financial instruments. “All the back office stuff can be simpler and more reliable, and they can save a tremendous amount of money,” explains David Yermack, professor of finance at New York University. “Today there are a lot of people working in banks just checking the work of other people.”
Security
Blockchains can also be used to create distributed contracts which can be used for keeping track of IOT devices, which were the main weapons used in a DDoS attack, and hence it can be seen as a step towards making the internet a secure place for everyone.
Meanwhile, healthcare is reaching an epic number of data security breaches over the past year including entire hospitals taken hostage by ransomware.
Decentralisation of entire web
With the rise of Internet giants like Google and Facebook, the Web’s power structure has become more centralized than many of its earliest adopters would like.
A startup called Blockstack wants to change that. Later this(2017) year it will release software, based on the digital ledger known as blockchain, that will enable your regular browser to explore a parallel universe to the Web where users have more control of their data.
You will still be able to load sites by clicking links or typing Web addresses. But instead of needing to create accounts with each site, users will control their own digital identity.