1.1.1 Variables and constants

• What are the two key components of a variable?

  Identifier and data type
• In Python, the statement x = 5 declares a variable with the value 5.
• What is the purpose of a data type in a variable declaration?

  Determines the type of value
• Initializing a variable means assigning an initial value when it is declared.
• What are the three types of variable scope?

  Global, local, block
• A global variable is accessible throughout the entire program.
• Where is a local variable accessible?

  Within a function
• Why is it important to initialize variables?

  Ensures data integrity
• Variable naming conventions are optional rules to improve code readability.
• What is the recommended case for variable names in most programming languages?

  Lowercase
• The underscore in total_price is an example of snake_case naming.
• Variable naming conventions are rules and best practices to ensure readability and maintainability.
• Constants are variables whose values can be changed during program execution.

  False
• In C++, constants are declared using the keyword const.
• Match the programming language with its constant declaration syntax:

  Python ↔️ CONST_NAME = value

  C++ ↔️ const data_type CONST_NAME = value;
• In Python, no explicit type declaration is needed for variables, whereas C++ requires it.
• Arrange the types of variable scope from broadest to narrowest:

  1️⃣ Global

  2️⃣ Local

  3️⃣ Block