Variables & Data Types

By the end, you can

• Explain the three parts of a variable and what reassignment does.
• Identify the type of any literal value (integer, float, string, boolean, or null).
• Describe why strings are immutable and what happens when you "change" one.
• Explain why 0.1 + 0.2 is not exactly 0.3 in floating-point arithmetic.
• Predict what the + operator produces when given two numbers versus a string and a number.
• Distinguish static typing from dynamic typing and give an example language for each.
• Choose the right data type for a given real-world variable (e.g., balance as float, phone number as string).