C# Access Modifiers Explained: Choosing the Right Visibility for Class Members

In C#, class members without an explicit access modifier default to private, while top-level classes default to internal. The language offers six main access levels — private, protected, internal, protected internal, private protected, and public — each controlling a different scope of visibility across classes and assemblies. A practical rule of thumb suggests keeping fields private and exposing them through properties, reserving internal for module-level sharing and public only for the class's intended contract. C# also allows separate access modifiers on property getters and setters, enabling fine-grained control such as a public getter paired with a private setter. This granularity supports the encapsulation principle of hiding data while still providing controlled read access, without requiring manual getter methods.