Namespaces are used in .NET to organize types, as well as for controlling the scope of types and methods in projects.

In Rust, namespace refers to a different concept. The equivalent of a namespace in Rust is a module. For both C# and Rust, visibility of items can be restricted using access modifiers, respectively visibility modifiers. In Rust, the default visibility is private (with only few exceptions). The equivalent of C#'s public is pub in Rust, and internal corresponds to pub(crate). For more fine-grained access control, refer to the visibility modifiers reference.