Machine Understandable code

The document discusses the four phases of compilation for a C program to become an executable: 1. Pre-processing removes comments, expands macros and includes. The preprocessed output is stored in filename.i. 2. Compilation converts filename.i into an assembly file (filename.s) with assembly instructions. 3. Assembly converts filename.s into an object file (filename.o) with machine-level instructions but unresolved function calls. 4. Linking resolves function calls by linking the object file with function definitions, adds startup/shutdown code, and creates the final executable file.