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SHA-1 is the most commonly used SHA algorithm, and produces a 20-byte hash value. Reference: https://www.securityinnovationeurope.com/blog/page/whats-the-difference-between-hashing-and-encrypting

Reference: http://www.btcsatoshi.com/

Proof of Stake has the same goal as proof of work—to validate transactions and achieve consensus in the chain—and it uses an algorithm but with a different process. With proof of stake, the creator of a new block “is chosen in a deterministic way, depending on its wealth, also defined as a stake.” Since in a proof of stake system, there is no block reward, but the miners, known as forgers, get the transaction fees. Proponents of this shift, including Ethereum co-founder Buterin, like proof of stake for the energy and cost savings realized to get to a distributed form of consensus.  Reference: http://www.hl.co.uk/news/2018/2/16/a-brief-history-of-blockchain-technology-everyone-should-read

A Byzantine failure is the loss of a system service due to a Byzantine fault in systems that require consensus. Reference: https://en.wikipedia.org/wiki/Byzantine_fault_tolerance

Stream cipher basically means using a fixed key which replaces the message with a pseudorandom string of characters. It is basically the encryption of each letter one at a time. Reference:https://blockgeeks.com/guides/cryptocurrencies-cryptography/

A logic gate usually takes in 2 inputs and gives out 1 output. The inputs and outputs are binary values, meaning they can be 1 or 0. A XOR logic gate takes in 2 binary inputs and gives out a high output ONLY when the inputs are different. Meaning, if A and B are inputted to a XOR gate then the out C will be 1 ONLY when A is not equal to B.  Reference: https://blockgeeks.com/guides/cryptocurrencies-cryptography/

Permissionless - anyone can join Anyone can run a node, run mining software/hardware, access a wallet and write data onto and transact within the blockchain (as long as they follow the rules of the bitcoin blockchain). There is no way to censor anyone, ever, on the permissionless bitcoin blockchain.  Reference: https://medium.com/@dustindreifuerst/permissioned-vs-permissionless-blockchains-acb8661ee095

Corda does not share the same requirements as Bitcoin: we require absolute certainty over transaction finality and we need to know who our counterparts are. So we had the freedom – and took this opportunity – to solve the consensus problem in a different way. In particular, Corda solves the privacy issue in a number of manners, primarily by allowing for separation of consensus into a service which we call the Notary Cluster. Corda was designed for business from the start. It has no cryptocurrency built into the platform and does not require mining-style consensus, which imposes great cost with little business benefit.

SHA stands for Secure Hash Algorithm. This is used to prove data integrity. The same input(s) will always produce the exact same output. This output is always 256 bits or 32 bytes in length regardless of the length of the input (even if input is millions of bytes).  Reference: https://medium.com/all-things-ledger/bitcoins-implementation-of-blockchain-2be713f662c2

Reference: https://solidity.readthedocs.io/en/latest/introduction-to-smart-contracts.html#the-ethereum-virtual-machine