Introduction

The source code consists of the programming statements that are created by a programmer with a text editor or a visual programming tool and then saved in a file. For example, a programmer using the C language types in a desired sequence of C language statements using a text editor and then saves them as a named file. This file is said to contain the source code. It is now ready to be compiled with a C compiler and the resulting output, the compiled file, is often referred to as object code.

The object code file contains a sequence of instructions that the processor can understand but that is difficult for a human to read or modify. For this reason and because even debugged programs often need some later enhancement, the source code is the most permanent form of the program.

What is Source Code?

Source code is a human-readable text written in a specific programming language. The goal of the source code is to set exact rules and specifications for the computer that can be translated into the machine’s language. As a result, source codes are the foundation of programs and websites.

In other words, Source code is the fundamental component of a computer program that is created by a programmer. It can be read and easily understood by a human being. 

When a programmer types a sequence of C programming language statements into Windows Notepad, for example, and saves the sequence as a text file, the text file is said to contain the source code. 

What you need to know about Source Code

• The source code is a collection of computer instructions written using a human-readable programming language.
• It is a high-level type of code.
• The source code is readable by the human or the programmer.
• Machines cannot directly understand a source code unless translated.
• A source code performs way less than the object code because it is not very close to the machines.
• It is not a system-specific type of code.
• Source code can easily be modified.
• The source code acts as the input to an assembler, compiler or any other type of translator.
• Source code exists in plain text. It is because we write it using a high-level type of programming language.
• Any human can understand a source code.
• It is written in high-level language like C, C++, Java, Python etc or assembly language.
• It contains less number of statements than object code.
• You can easily change the source code over the course of time.

What is Object Code?

Object code is a set of instruction codes that is understood by a computer at the lowest hardware level. Object code is usually produced by a compiler that reads some higher level computer language source instructions and translates them into equivalent machine language instructions.

In other words, Object code is produced when an interpreter or a compiler translates source code into recognizable and executable machine code.

Object file contains object code. Some object file examples are common object file format (COFF), COM files and “.exe” files. It is the output of a compiler or other translator. We can understand source code but we can not understand object code as it is not in plain text like source code rather it is in binary formats.

What you need to know about object code

• The object code is a sequence of statements in machine or binary, and is the output after the compiler.
• It is a low level type of code.
• The object code is readable by the computer.
• Any machine can directly understand as well as execute an object code.
• An object code performs more and better than the source code because it is comparatively very close to the machines.
• It is a system-specific type of code as it easily runs on machines.
• Object code cannot be modified.
• The object code acts as the output of an assembler, compiler or any other type of translator.
• Object code exists in binary format. It is because it is a translated form of code that roots from the source code.
• A machine can understand an object code- not a human.
• It is written in machine language through compiler or assembler or other translator.
• It contains more number of statements than source code.
• You need to compile the source code or translate it using any other translator after making the necessary changes- so that it reflects in the recent object (modified code).

Compiler And Interpreter

For the computer to be able to further process the source code written by the programmer, there needs to be a translation between the two – this occurs in the form of an additional program. This assistance application can be in either the form of a compiler or an interpreter:

• Compiler: This application type translates (compiles) the source code into a code that the process understands and can execute. This machine code is saved in the form of an executable file.
• Interpreter: An interpreter translates the source code line for line and executes it directly. The translation process is much faster than a compiler but the execution is slower and requires a large amount of memory.

Also Read: Difference Between Procedural And Object Oriented Programming

Difference Between Source Code And Object Code In Tabular Form

Conclusion

Source code is the list of human-readable instructions that a programmer writes—often in a word processing program—when he is developing a program. The source code is run through a compiler to turn it into machine code, also called object code, that a computer can understand and execute. Object code consists primarily of 1s and 0s, so it isn’t human-readable. 

Source code and object code are sometimes referred to as the “before” and “after” versions of a compiled computer program. For script (no compiled or interpreted) program languages, such as JavaScript, the terms source code and object code do not apply, since there is only one form of the code.