Working with C is like working with most programming languages. First, you write a program using an editor. Next, you compile your program, translating it into machine instructions.
In its original form, your program is called text or source code. Once translated, the source code becomes object code.
Your program's source code may be distributed among several files, which you can compile into separate object-code files. Subsequently, you link the separately compiled object-code files to produce executable code.
Finally, you run your executable code, or, said another way, you execute your program.