This was an introduction to why blockchain, decentralization, and what exactly is a smart contract is as an overview. Following is the small notes of what I have learned in this

Bitcoin

• First protocol to use blockchain
• Powered by cryptography
• Digital store of value aka a digital goldmine
• It is in scarce quantity

Smart Contract

• Smart contracts allow for agreements without centralized intermediaries
• These are the self-executing sets of instruction, without the 3rd parties

Decentralized And Hybrid Application

• The Oracle Problem - Everything that happens in the blockchain is in a small box, needs real-world data.
• To fetch the real word data the decentralized application must go hybrid and contact third parties outside of their blockchain network

Following are the advantages of the decentralized application:

• No central authority - No one can turn off a switch and stop you from doing what you want to do
• Transparency & flexibility - Everything that happens in the blockchain is visible to everyone
• Speed and Efficiency - The time it takes to respond to a certain task is less
• Security & Immutability - Blockchains are immutable (state cannot be changed once done), which makes them secure
• Removal of counterparty risk: Imagine taking insurance and the insurance company doesn't pay your bills, the decentralized application removes these kinds of risks
• trust minimized agreements (Math-based agreements): centralized applications are trust based as our confidence is directly associated with the central authority example - loans, insurance, aggreements. Now, in the case of blockchain, everything is math-based, as everything happens in code.