Best Practices for Naming in Programming: Avoiding Common Pitfalls

One of the most famous quotes in computer science is:

“There are only two hard things in computer science: cache invalidation and naming things.”

Here’s a generated index table that you can include for your article on naming conventions in programming:

Index	Description
Introduction	Overview of the importance of naming in programming and the famous quote: “There are only two hard things in computer science: cache invalidation and naming things.”
Avoid Single-Letter Variables	Why single-letter variable names should be avoided and how to use descriptive names instead.
Avoid Abbreviations	Explanation on why abbreviating variable names is a bad practice and how to use full, descriptive names.
Don’t Include Types in Variable Names	A breakdown of why including types (Hungarian notation) in variable names is unnecessary in modern languages.
Include Units in Variable Names	The importance of including units in variable names for clarity, and examples of how to do so effectively.
Avoid Prefixing Interfaces and Base Classes	Discussion on why prefixing interfaces with “I” and base classes with “Base” adds noise and how to avoid it.
Avoid Utility (Utils) and Helper Classes	Explanation on why grouping functions into utility or helper classes is an anti-pattern, and how to better structure your code.
Conclusion	Summary of best practices for naming conventions and a call to consider naming conventions as a fundamental part of writing maintainable code.

This table helps readers navigate the article quickly and find sections relevant to them.

While it might sound simple, naming things in code can be surprisingly challenging. It’s easy to fall into bad naming habits, which can hinder readability and maintainability. However, by avoiding common bad practices, we can get 80% of the way to better naming conventions. Let’s dive into what these bad practices are and how to avoid them.

Avoid Single-Letter Variable Names

The first and most basic rule is to never use single-letter variable names. This issue likely stems from the mathematical roots of computer science, where mathematicians prefer brevity. However, code needs to be readable, and a single letter doesn’t provide any meaningful context.

Bad Example:

int x = 10;

Better Example:

int userAge = 10;

In the second example, it’s immediately clear that the variable represents an age, making the code more understandable at a glance.

Why This Matters:

You spend more time reading code than writing it. Single-letter variable names don’t give any clue about what the variable is used for, which slows down comprehension, especially for new developers joining the project.

Avoid Abbreviations

Even though it can be tempting to abbreviate variable names to save keystrokes, this practice should be avoided. Abbreviations are context-dependent and can be confusing to those unfamiliar with the naming pattern used. The days of typing on tiny 80-character-wide screens are over, and modern editors make writing long variable names much more manageable.

Bad Example:

def calcTtl(prc, qty):
    return prc * qty

Better Example:

def calculateTotal(price, quantity):
    return price * quantity

Why This Matters:

Abbreviations introduce ambiguity. Someone reading your code for the first time shouldn’t have to guess what prc or qty means. Descriptive, full names make the code easier to read and maintain.

Don’t Include Types in Variable Names

A common older practice, especially in languages like C, was to include types in variable names. This was known as Hungarian notation. However, with modern statically typed languages like C# or Java, the type system already provides this information, so there’s no need to add it to your variable names.

Bad Example:

int iUserAge = 25;

Better Example:

int userAge = 25;

Why This Matters:

The type system in most modern languages handles type declarations, making type prefixes redundant. Let the language handle types—focus on naming variables based on their purpose, not their type.

Include Units in Variable Names

While it’s unnecessary to include types in your variable names, it’s good practice to include units when they provide useful context. For example, if a function accepts a delay time, you should specify the unit in the variable name.

Example:

public void Delay(int delaySeconds) { }

Even better, in languages like C# and C++, you can use types that encapsulate time spans, such as TimeSpan or chrono::duration, respectively.

Example in C#:

public void Delay(TimeSpan delayTime) { }

In this case, you don’t even need to specify the unit, as the TimeSpan object handles that for you. This leads to fewer bugs because the type system enforces correctness.

Avoid Prefixing Interfaces and Base Classes with Types

In C#, there’s a pattern of prefixing interfaces with “I” and naming base classes as “BaseClassName”. While this might seem helpful, it’s usually unnecessary. Users of an interface don’t need to know whether it’s an interface, abstract class, or concrete class—they just need to know what it does.

Bad Example:

public interface IAnimate { }
public class BaseTruck { }

Better Example:

public interface Animate { }
public class Truck { }

If you need to differentiate between child classes, be more specific:

public class TrailerTruck : Truck { }

Why This Matters:

Prefixing types with “I” or “Base” adds unnecessary noise. The focus should be on what the class or interface does, not on its underlying type.

Avoid Utility (Utils) and Helper Classes

A common anti-pattern is bundling a bunch of unrelated functions into a “utils” or “helper” class. While this might seem convenient, it often leads to messy, difficult-to-maintain code.

Bad Example:

class MovieUtils:
    def get_movie_title(movie):
        return movie.title

    def paginate_movies(movie_list):
        # pagination logic

Better Example:

Instead, these functions can often belong to more specific classes:

class Movie:
    def get_title(self):
        return self.title

class MoviePaginator:
    def paginate(self, movie_list):
        # pagination logic

By splitting out utility methods into their relevant classes, each class has a clearer, more focused responsibility, making the code more modular and easier to maintain.

Conclusion

Good naming practices are essential for writing readable, maintainable code. By avoiding common pitfalls like single-letter variables, abbreviations, and utility classes, you force yourself into better habits that make your code easier for both you and others to understand. Here’s a quick recap:

• Avoid single-letter variables: Use meaningful names that describe the variable’s purpose.
• Avoid abbreviations: Full names reduce ambiguity and make code clearer.
• Don’t include types in variable names: Let the type system do the work.
• Use units in variable names: Clearly indicate units to avoid confusion.
• Avoid unnecessary prefixes (I, Base): Focus on the functionality, not the type.
• Avoid utils and helper classes: Place functions in appropriate, descriptive classes.

By adhering to these rules, you’ll write code that’s not only functional but also easy to read, maintain, and extend.

What other naming conventions do you find useful? Share your thoughts!