“Give me six hours to chop down a tree and I will spend the first four sharpening the axe.”
— Abraham Lincoln
A master tailor doesn’t start with scissors and fabric—they start with a pattern. Not because they can’t design from scratch, but because generations of experience have shown them what works. These patterns act like blueprints: they’re tried-and-true guides for building something that fits, functions, and lasts.
Software engineers aren’t so different. Instead of scissors and thread, we work with code and logic—but we also rely on patterns. Design patterns in software are not sequences of shapes or visuals; they’re abstract solutions to recurring design problems in programming. They’re not code snippets to copy but strategic structures you can adapt and reuse. They’re how we “sharpen the axe.”
In technical terms, a design pattern is a general repeatable solution to a commonly occurring problem in software design. The term was popularized by the “Gang of Four” (Erich Gamma, Richard Helm, Ralph Johnson, and John Vlissides) in their classic book Design Patterns: Elements of Reusable Object-Oriented Software. These patterns—like Singleton, Factory, Observer, and Strategy—offer guidance without dictating the exact implementation.
Think of them like sewing patterns: they don’t tell you what fabric to use or what color to pick, but they give you a structure for making something functional and stylish.
In our own class projects, design patterns have subtly influenced the way we build. For example, during the digits project, we reused the same HTML/JavaScript structure across multiple pages. Rather than write unique logic for each digit, we followed a common page template—a real-life use of the Template Method Pattern, where the structure stays the same but specific content changes.
Now, with our final project, the patterns are getting more advanced. We’re using components that update dynamically as data changes, an example of the Observer Pattern. We’ve written generalized functions to create different page elements, another nod to the Factory Pattern. These patterns help us manage complexity, improve code readability, and avoid repeating ourselves.
When you know design patterns, you’re not just solving problems—you’re solving them in a way others can understand. They create a shared language between developers. Saying, “I used a decorator here,” communicates volumes more than a paragraph of explanation.
Much like a well-used sewing pattern saves time and avoids error, design patterns give us tools to build efficiently and maintainably. They’re not dogma—they’re best practices refined by experience.
This essay was written with help from ChatGPT