Concepts | Concept Map

• What is a VM?
• Virtualization
• State Machines
  • Ethereum Distributed State Machine
    • State Transition Function
    • Transactions
• EVM
  • Stack machine
  • Op Codes
• Compilation

EVM

• Global singleton
  • Operates as if it were a global, single-instance computer, running everywhere
  • In computer science design patterns, the singleton pattern ensures that a class has only once instance and provides a global point of access to that instance
    • Real world non-computing example: Government - A country can have only one official government
    • Singleton pattern solves two problems
      • Ensure that a class (or something) has just a single instance
        • Control access to one shared resource such as a file or a database
      • Provide a global access point to that instance
        • But instead of global variables, which are unsafe, and are at risk of being overwritten, the Singleton protects the instance from being overwritten by other code