At a high level, the key difference is who gets to participate and who controls access to the blockchain.
Permissioned Blockchain (aka Private Blockchain)
Access is restricted: Only selected participants can join the network.
Governance is centralized or consortium-based: One company or a group of approved entities controls validation rights.
Use case: Ideal for enterprises, supply chains, banking, or healthcare where privacy, compliance, and performance are critical.
Examples: Hyperledger Fabric, R3 Corda, Quorum.
Think of it like a corporate intranet secure, controlled, and tailored for internal stakeholders

Permissionless Blockchain (aka Public Blockchain)
Open to everyone: Anyone can join, read, write, or validate transactions.
Decentralized governance: Network rules are enforced through consensus mechanisms (like proof-of-work or proof-of-stake).
Use case: Cryptocurrencies, DeFi, DAOs where transparency and censorship-resistance are the goal.
Examples: Bitcoin, Ethereum, Solana.
Think of it like the public internet no barriers to entry, but also no control over who participates.
Here is my final thought
The choice between permissioned and permissionless boils down to trust vs. transparency.
Enterprises often choose permissioned for performance, privacy, and compliance.
Startups and Web3 builders lean toward permissionless for openness, innovation, and community-first growth.