🧑‍💻 Fundamental Concepts

Every Java program, no matter how complex, is built out of the same small set of building blocks: a place to start executing, values to work with, and ways to name, combine, and move those values around. Before you can write control flow, classes, or robot code, you need to be comfortable with these basics.

This section covers the foundation everything else in this guide builds on:

• Program Skeleton: The standard structure every Java file follows and where execution begins
• Data Types: The built-in kinds of values Java can represent, and how they're stored
• Floating Point: Why decimal values can't always be represented exactly, and what that means for your code
• Variables: Naming and storing values so they can be reused and changed
• Constants: Values that are fixed once they're set
• Expressions: Combining values and operators into something that evaluates to a result
• Operators: The symbols Java uses to compute, compare, and combine values
• Type Casting: Converting a value from one data type to another
• I/O: Getting input into a program and sending output back out