C++ struct vs class: The one technical difference and when to use each

A junior C++ learner explains that struct and class in C++ are functionally identical, with one key distinction: struct members are public by default, while class members are private by default. This single rule also extends to inheritance, where struct uses public inheritance by default and class uses private inheritance, a common source of beginner errors. Beyond the technical difference, the author recommends using struct for simple data containers with no internal rules to enforce, and class for objects that encapsulate behavior and protect their internal state. Practical examples include using struct for a Point or Config bundle, and class for a BankAccount or Stack that must maintain data integrity. The post also notes that struct remains the better choice when writing code intended to be compatible with C.