Programming Fundamentals Week 3: Simple Data Types and Variables

Valid Variable Names

• A valid variable name must begin with a letter (a-z, A-Z) or an underscore (_).
• Subsequent characters can include letters, digits (0-9), and underscores.
• Variable names are case-sensitive, meaning "Variable" and "variable" are different.

Invalid Variable Names

• Names that start with a digit are invalid (e.g., 1variable).
• Special characters like #, @, $, or spaces are not allowed.
• Variable names cannot be too long or exceed language-specific limits.

Reserved Words

• Reserved words (keywords) are predefined in programming languages and cannot be used as variable names (e.g., if, else, while).
• Attempting to use reserved words as variables will result in errors.

Allowed Special Characters

• Only underscores (_) are allowed in variable names, aside from letters and digits.
• No other special characters (e.g., &, %, -, +) can be included in variable names.

Learn about simple data types, variables, constants, arithmetic operators, escape sequences, and the rules for naming variables in programming fundamentals. Explore how to declare and use different types of variables in your code.