C is a general-purpose, high-level language that was originally developed by Dennis M. Ritchie to develop the UNIX operating system at Bell Labs. C was originally first implemented on the DEC PDP-11 computer in 1972.
C# is a simple, modern, general-purpose, object-oriented programming language developed by Microsoft within its .NET initiative led by Anders Hejlsberg.
The following are the differences between C and C#.
C language is a structured programming language, whereas C# is an object-orinted language.
C has manual memory management, whereas memory management is handled automatically in C#.
C do not have a garbage collector whereas C# has CLR for garbage collection.
C program can be run on different platforms whereas C# is generally used only on Windows and needs the .NET framework.