What Is Source Code? How Source Code Works

a green background with repeating question marks across it: what is source code

If you’re an ecommerce entrepreneur, your online store—the shopping carts, payment gateways, and even the algorithms that offer customers personalized recommendations—are all governed by underlying instructions called source code.

Source code isn’t just the domain of developers and coders; understanding it can provide critical insights into your business operations and can help you ensure your online store works to meet your business goals and customer needs. Here’s a brief primer.

What is source code?

Source code is a programmer’s instructions—written in a computer programming language—telling a computer how to execute specific tasks, from displaying text and images to carrying out complex computations. It’s the invisible backbone of software. Despite source code’s hidden nature, it powers every website, app, and digital tool you use and shapes your interaction with the digital world.

As an ecommerce business owner, understanding source code isn’t strictly necessary. Platforms like Shopify offer user-friendly interfaces that allow you to create and manage your store without writing code. The rise of low-code and no-code tools has also made it easier for non-tech-savvy users to build complex applications, like custom customer relationship management systems or interactive dashboards to visualize sales metrics. 

However, a basic understanding of source code can help you better communicate with developers on your team or troubleshoot minor issues in a pinch, like fixing a typo on your website, correcting broken image links, or changing the text on a button.

How to write basic source code

Programmers write source code using programming languages to translate their logic into commands computers can understand and execute. This source code is the foundation of all computer programs and digital systems—from operating systems that manage hardware to inventory management systems that track products.

Here’s a step-by-step breakdown of the process of writing source code:

1. Write the source code

Programmers write source code using a computer programming language, like Python, Java, C++, Ruby, or JavaScript, among many others, in a text editor or an integrated development environment (IDE). (A text editor is a basic software program for editing plain text files, while an IDE is a more robust application designed for writing and testing code.) The source code serves as the instructions for the computer program.

2. Save the source code

After you’ve written source code, you can save it on your computer’s hard disk. From there, you can share it and work on it with collaborators. Saving files also facilitates version control and backup. Depending on the program’s complexity, these files can contain anything from a few lines of code to thousands of lines of code.

3. Compile the source code

Next, compile the source code using tools like a C compiler. Compilers translate the human-readable source code into binary or machine code—strings of 1s and 0s, machine language the CPU understands.

4. Generate object code

The compiler generates object code from the source code. The computer’s operating system can directly execute this object code. When the operating system executes the object code, it loads it into memory, and the CPU carries out the programmed instructions in order, allowing the computer to perform the desired tasks.

5. Execute the program

The computer reads the object code and executes the instructions in the computer program. For example, an ecommerce website’s object code may include instructions to display product photos and descriptions when a user loads a product page. Alternatively, a shopping cart page’s object code might contain logic to calculate total costs and applicable taxes when users add items.

Source code examples

The source code example below uses the C programming language. When run, the source code instructs the computer to display the message “Welcome to your digital shopping destination!”

#include <stdio.h>

int main() {

printf("Welcome to your digital shopping destination!\n");

return 0;


This source code example uses the Python language. Similarly, when run, the source code tells the computer to display the text “Welcome to your digital shopping destination!” 

print("Welcome to your digital shopping destination!")

Types of source code

Different programming languages serve unique functions and can contribute to creating the digital storefront your consumers interact with. Understanding this source code can help you grasp the inner workings of your ecommerce platform. 

Here are a few essential programming languages and their roles:


HTML and CSS are key in forming an ecommerce website’s look and feel. HTML structures the site, and CSS controls styling and layout. Programmers write source code in these languages to determine how a web page displays text, images, and other elements.


JavaScript is a useful language for creating interactive elements in a computer program, especially for ecommerce websites. JavaScript allows computer programmers to enhance web interactivity and produce dynamic content, like offering pop-ups and customer help desk widgets, making the shopping experience more engaging.


Python is a go-to computer programming language for the back end of many ecommerce websites. Using an integrated development environment, developers write source code in Python to quickly construct robust and scalable web applications, including back end user authentication, authorization, and payment processing. 


Frequently implemented in web development, PHP powers several ecommerce platforms and is known for its seamless integration with HTML and extensive database support.

Ruby (Ruby on Rails)

Clean and easy to understand, Ruby, especially with the Rails framework, is used on ecommerce platforms like Shopify to create durable and scalable applications. Ruby on Rails is an open-source web application framework built in the Ruby language, providing default structures for databases, web services, and websites to help developers quickly build new applications.


Java is also often used for developing the back end of ecommerce sites due to its robustness, scalability, and security features. Java helps build reliable server-side systems that handle significant web traffic without crashing or slowing down.

Common uses of source code

From providing a blueprint for constructing dynamic websites to acting as an educational tool for budding programmers, source code’s applications are as diverse as they are integral.

Building the foundation of a website

Source code files are the building blocks of a website. They contain instructions for the site’s layout, appearance, and functionality. Developers can write code to create HTML pages, style them with CSS, and make them interactive with JavaScript. The quality of this code directly affects the website’s performance, security, and user experience.

Adding a specific function to a program

Every feature or function of a software program starts as an idea translated into source code. If a developer wants to add a new feature to a program, they write code that implements this feature and then integrate this code into the existing program’s source code. 

Only the software authors or trusted contributors can modify the code to maintain code quality and ensure the program functions as expected. The new code is often saved in a single file before being compiled into binary code, which the computer can execute.

Creating algorithms

Source code serves as a medium for developers to create and share algorithms—sequences of instructions for performing tasks. By writing source code in a universal computer programming language, you can convey complex instructions. 

Source code FAQ

What is source code licensing?

Source code licensing is the legal framework that governs how others can use, modify, or distribute the software’s source code. Different types of licenses dictate varying levels of accessibility and rights.

Can I see the source code of any website?

Yes, the client-side source code of any website, which includes HTML, CSS, and JavaScript, can be viewed using your web browser’s Inspect or View Source options. However, server-side source code isn’t publicly accessible.

How important is source code security?

Source code security is crucial. It helps prevent unauthorized access, protects intellectual property, and maintains your software's integrity, preventing vulnerabilities that hackers could exploit.

What is the difference between open-source and proprietary source code?

Open-source source code is publicly accessible, allowing anyone to view, use, modify, or distribute it. Proprietary source code, however, is owned by an individual or a company, and its access, use, and distribution are restricted and governed by specific licensing terms.

How can I protect my source code from unauthorized access or theft?

Implement robust security measures like access control, encryption, and regular audits to protect your source code. Consider using a source code repository for added security, and ensure your licensing terms explicitly state your code’s usage restrictions.