Before we dive into the types of blockchain, we must get familiar with the concept of the permission spectrum of distributed ledger technology aka DLT. A blockchain is a DLT and exists throughout the permission spectrum.
To understand the permission spectrum, we need to identify the two extreme ends of this spectrum. At one end, we have to seek complete permission from an entity to participate in a consensus, and at the other extreme, we do not have to seek any permissions whatsoever from any entity to participate in a consensus.
The interesting thing about the permissionless extreme is that we have no obligation to reveal our identity to anyone participating in the consensus. As we move toward complete permission, somewhere in the mid-spectrum of permission, this identity aspect needs to be revealed in order to participate in a consensus, just to validate our stakes in a consensus. As we arrive at the complete permission, we need to identify ourselves as well as take permission...