Elements of the Ethereum blockchain

In the following section, you will be introduced to various components of the Ethereum network and the blockchain. First, the basic concept of the EVM is given in the next section.

Ethereum virtual machine (EVM)

EVM is a simple stack-based execution machine that runs bytecode instructions in order to transform the system state from one state to another. The word size of the virtual machine is set to 256-bit. The stack size is limited to 1024 elements and is based on the LIFO (Last in First Out) queue. EVM is a Turing-complete machine but is limited by the amount of gas that is required to run any instruction. This means that infinite loops that can result in denial of service attacks are not possible due to gas requirements. EVM also supports exception handling in case exceptions occur, such as not having enough gas or invalid instructions, in which case the machine would immediately halt and return the error to the executing agent.

EVM is a fully isolated...