Consensus algorithms, such as Proof-of-Work or Proof-of-Stake, are the core security mechanisms in blockchain technology. They ensure that all participants in the network agree on the validity of transactions and blocks, preventing malicious actors from manipulating the blockchain.

A 51% attack occurs when an attacker gains control of more than 50% of the network's hash rate, allowing them to manipulate the blockchain by adding or removing transactions, or even reversing blocks.

Smart contract vulnerabilities are a common type of blockchain security issue, where malicious code within a smart contract can allow an attacker to steal funds, manipulate data, or disrupt the operation of the contract.

A blockchain explorer is a tool that allows users to view and interact with blockchain data, such as transaction history, block information, and wallet balances. It provides a user-friendly interface to explore the blockchain and its contents.

Blockchain technology is being used to facilitate cross-border payments, enabling faster, cheaper, and more transparent transactions between parties in different countries.

A double-spending attack occurs when an attacker spends the same coins twice, typically by manipulating the blockchain or exploiting vulnerabilities in the network.

Reentrancy attacks are a type of smart contract attack where an attacker exploits a vulnerability in the contract's code to call the contract multiple times, allowing them to manipulate the contract's state and potentially steal funds.

A blockchain wallet is a software or hardware device that stores and manages blockchain keys, which are used to access and control funds on a blockchain.

Blockchain technology is being used to track the movement of goods and materials throughout the supply chain, providing greater transparency, traceability, and efficiency.

A blockchain fork occurs when a new blockchain is created from an existing blockchain, typically due to disagreements or the desire to implement new features or rules.

51% attacks are a type of blockchain security attack where an attacker gains control of a majority of the network's hash rate, allowing them to manipulate the blockchain and potentially reverse transactions.

A blockchain smart contract is a self-executing contract with the terms of the agreement directly written into lines of code. It automatically executes the terms of the contract when predetermined conditions are met.

Blockchain technology is being used to manage patient medical records, providing secure and tamper-proof storage and access to sensitive health information.

A blockchain consensus algorithm is a mechanism used to achieve agreement among participants in a blockchain network on the validity of transactions and blocks. It ensures that all participants have a shared understanding of the state of the blockchain.

Sybil attacks are a type of blockchain security attack where an attacker creates multiple fake identities to gain disproportionate influence or control over the network.