Understanding the Open-Closed Principle with Example
Vikas Sood
January 12, 2026
Do you want to truly understand how software systems work? Smart Coder’s programming books are for you. Designed specially for computer science students and software developers, our books focus on system design, scalable architecture, and strengthening the fundamentals that matter in real software engineering.
Understand core programming concepts with simple explanations and practical examples for everyday coding.
Do technical interviews make you nervous, even when you know how to code? That hesitation usually doesn’t come from a lack of coding skills. It comes from unclear fundamentals.
Today, companies aren’t just looking for someone who can write code. They’re looking for engineers who can think, reason, and design systems.
Smart Coder’s programming eBooks help students and developers build this exact mindset. By learning core engineering concepts like SOLID principles, design patterns, and software architecture, you’ll understand why systems are designed a certain way—not just how to implement them.
We break down complex ideas using simple, real-world examples, making learning intuitive and practical. As a result, you’ll write cleaner code, make stronger design decisions, and build software that’s easier to maintain, extend, and scale.
Strong fundamentals lead to clear thinking. Clear thinking leads to confident interviews.
Smart Coder’s software programming books are designed to make complex engineering concepts simple, practical, and easy to apply. We focus on clarity over complexity, so you actually understand how and why things work, instead of just memorizing concepts.
Our ebooks break down complex topics like system design, SOLID principles, and software architecture using real-world examples that you can understand easily. This approach helps students and developers build strong fundamentals, think logically, and write cleaner, more structured code that scales as projects grow.
Learning system design is one of the most effective ways for students and developers to level up their skills. While writing code is important, understanding how software systems are structured helps you think beyond individual functions and start building solutions that scale. System design teaches you how different components interact, how data flows, and how decisions impact performance and maintainability.
Smart Coder’s programming books are designed to make system design approachable and practical. Our software programming books explain concepts like SOLID principles, design patterns, and software architecture using simple examples from real-world applications such as e-commerce platforms, messaging apps, and payment systems. This helps learners connect theory with real engineering problems they’ll face in projects and jobs.
Through our programming e books, students learn how to structure code better, reduce complexity, and design systems that are easier to extend over time. Developers, on the other hand, gain clarity on making better architectural decisions instead of relying on trial and error. With easy programming books download options, you can revisit concepts whenever needed and learn at your own pace.
These online programming books are built to support continuous upskilling. If you’re serious about growing from a coder into a well-rounded software engineer, system design is the skill that makes the difference.
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