Difference between class library and executables in C#

In C#, a class library and an executable are two different types of projects that serve distinct purposes within a software development context.

1. Class Library: A class library in C# is a collection of reusable classes, interfaces, enums, and other types that are designed to be used by other applications or projects. It contains functionality that can be referenced and utilized by multiple applications. Class libraries help promote code reusability, modularity, and maintainability.

   - Purpose:

     The main purpose of a class library is to encapsulate common functionalities, algorithms, or utilities that can be shared across various applications or projects. It provides a way to organize and distribute code in a structured and reusable manner.

   - Output:

     The output of a class library project is typically a compiled assembly (a .dll file), which contains the compiled version of the classes and other types defined within the library.

2. Executable: An executable in C# refers to a project that represents a standalone application that can be executed independently. This type of project is designed to have a starting point, usually a Main method, where the program's execution begins.

   - Purpose:

     The primary purpose of an executable is to provide a complete and functional application that can be run by end-users. It contains the entry point of the application and orchestrates the execution flow.

   - Output:

     The output of an executable project is an application or program (an .exe file) that can be executed directly by the operating system.

Key Differences:

1. Purpose:

   - Class libraries are designed to encapsulate reusable code and functionality for use in other applications.

   - Executables are standalone applications intended to be run independently by end-users.

2. Output:

   - Class libraries produce compiled assemblies (.dll files) that can be referenced by other projects.

   - Executables produce standalone application files (.exe) that can be executed by the operating system.

3. Execution:

   - Class libraries cannot be directly executed as they are meant to be used as components in other applications.

   - Executables can be executed directly by the operating system, and they have an entry point (Main method) where the program starts.

In summary, class libraries are building blocks that encapsulate reusable code, while executables are standalone applications that end-users can run directly.