Blockchain basics

Millions of transactions occur daily containing a lot of money taken under the table. This transaction data is stored somewhere in a database. But this database is incompletely reliable or secure.

The reasons behind this are -

1. There is no access to the database.
2. The data inside the database can be altered anytime by the admin.

A system with decentralized access, where everyone has a shared authority and raised security where changing data is difficult, could gain more trust. Blockchain is such a system. To understand blockchain in a better way, let’s take an example of a supermarket. A supermarket always maintains the records of all the stocked goods and the sold goods along with their whereabouts. These records are called ledgers. Blockchain is just like the ledger, and each block is a single record inside the ledger.

The first block of the blockchain system is called the genesis block. Each block connects to another block forming a chain of blocks.

A single block consists -

1. Data: Information relevant to the use case of a specific blockchain; For instance, transaction data when using bitcoin in the blockchain.
2. Hash: Hash is a unique code for the data stored in that block.
3. Previous Hash: It is the hash of the previously linked block.

To summarise in a line, the hash keeps the data unique, while the previous hash tracks the block backward.

It is hard to change the data inside the blockchain. If data inside a block is changed, its hash changes. Prev Hash present inside the next block is hence changed. These changes make all the further data invalid.

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Today, multiple domains use blockchain, cryptocurrency being one on the top. Crypto is a virtual/digital currency that runs on the Blockchain system. Bitcoin is the most widely used cryptocurrency. These blockchains don’t need mediators like banks, online wallets, or third-party applications to carry out transactions.

For example, If I want to transfer money to someone outside India, I would send rupees which would convert to other currency via banks or apps. These banks or apps charge high conversion charges, but in crypto, bitcoin is sent directly, with minimal fees. Just like gold, bitcoin transfers from asset to asset. Hence, the conversion won’t take place.

Careers in blockchain are booming now. Various startups and businesses use blockchain and need skilled blockchain developers.

Lastly, here are some links to the roadmap to get your career started in blockchain technology.

Hindi Channels

1. Anuj Bhaiyya:- https://youtu.be/KbQ5XMsKplI
2. Apna College:- https://youtu.be/uULy2rc6YDc
3. Ishan Sharma:- https://youtu.be/6SGbc8eJzEY

English Channels

1. Tiff in Tech:- https://youtu.be/VA-46Goc0e4
2. Dapp university:- https://youtu.be/uGPC9wNTBbw
3. Morlis Web3:- https://youtu.be/P87pLayUD8c

Podcast On Blockchain & Crypto

The Ranveer Show:- https://youtu.be/qeMmxq0MT6g

Credits: I learned a lot about Blockchain from Apna College Youtube Channel.