Summary  
This chapter explains how to assign default values to parameters and perform null checks to prevent null reference errors and ensure robust code execution.

General domain of usage  
Input validation

Master the essentials of variables and data types in Dart. This course guides absolute beginners through Dart's variable declarations, type inference, core data types, and null safety, using engaging explanations and real-world themed challenges.

Explore how to declare variables in Dart, the difference between var, final, and const, and how type inference works compared to explicit typing.

Dive into Dart's essential data types: int, double, bool, String, and num. Learn how and when to use each type.

Understand Dart's approach to null safety, including nullable and non-nullable types, default values, and null checks.

Default Values and Null Checks