What is the first step in debugging code?

The first step is to read the error message carefully and identify exactly where and when the problem occurs, rather than guessing at a fix before understanding what's actually going wrong.

Why is printing variable values a useful debugging technique?

Printing variable values at different points in your code lets you see the actual state of your program as it runs, helping you pinpoint exactly where the behavior diverges from what you expected.

5 Debugging Habits That'll Save You Hours of Frustration

July 6, 2026 6 min read

Every programmer, no matter how experienced, spends a significant chunk of their time debugging. The difference between someone who debugs efficiently and someone who spends hours randomly guessing usually comes down to a handful of habits. Here are five worth building early.

1. Actually Read the Error Message

It sounds obvious, but it's the single most skipped step. Error messages usually tell you the type of error, the file, and often the exact line number where things went wrong. Beginners frequently glance at an error, feel overwhelmed by the wall of text, and start guessing at fixes without reading what the computer is actually telling them.

Slow down and read it properly. A message like TypeError: cannot read property 'name' of undefined is telling you something specific happened, you tried to access .name on something that turned out to be undefined. That's a concrete, searchable clue, not just noise.

2. Reproduce the Problem Reliably

Before trying to fix anything, make sure you can reliably trigger the bug. If a bug only happens sometimes, or you're not sure exactly what causes it, you'll waste time "fixing" things that were never the actual problem, and won't be able to confirm your fix actually worked.

3. Isolate the Problem

Instead of staring at your entire program trying to spot the issue, narrow down where the problem actually lives. Comment out sections of code, or test small pieces in isolation, until you've cornered the specific function or line responsible. A bug in a 500-line file feels overwhelming; a bug you've narrowed down to three lines is usually easy to spot.

4. Print Values as You Go

Adding temporary print statements (or using a proper debugger) to check what your variables actually contain at different points is one of the most reliable ways to find the gap between what you expect your code to do and what it's actually doing. If you expected a variable to hold 5 and it's printing undefined, that mismatch tells you exactly where to focus.

Don't assume you know what a variable contains, verify it directly. Assumptions are where most debugging time gets wasted.

5. Change One Thing at a Time

When you're trying a fix, resist the urge to change five things at once hoping one of them works. If it does work, you won't know which change actually fixed it, and if it doesn't, you've now got five new variables to untangle. Make one change, test it, and only move to the next idea if that one didn't work.

Putting It Together

Debugging efficiently isn't about being naturally gifted at spotting bugs, it's a systematic process: read the error carefully, reliably reproduce the issue, narrow down where it lives, verify your assumptions about variable values, and test changes one at a time. Building these habits early saves enormous amounts of time over the course of a programming career, and it's one of the most transferable skills across every language you'll ever work in.

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