A source file is a text file that contains the source code of a program. It is usually written in a programming language such as C, C++, Java, or assembly language.
The source code is the set of instructions that a programmer writes in order to create a program. A programmer writes the source code in a text editor, and then saves the file with a .c, .cpp, .java, or .s extension.
The source file is one of the most important files in a software project. It is the starting point for the compiler, which converts the source code into object code (also called machine code or executable code).
Object code is a binary representation of the source code that can be run on a computer. The compiler creates an object file for each source file it processes.
When a programmer makes changes to the source code, they need to recompile it in order to create an updated version of the program. This process is known as compiling. The compiler can also be used to create programs from scratch by starting with an empty source file.