Debugging & Errors
How to Fix npm install Errors
ERESOLVE, EACCES, node-gyp, ENOENT, integrity failures: the npm install errors that account for almost every failure, what each means, and the fix…
Debugging & Errors
Your code broke and you do not know why. These guides explain what error messages mean, how to read a stack trace, and what to check first.
15 guides
Debugging & Errors
Fixing “externally-managed-environment” When Using pip
pip refuses to install into the system Python on Ubuntu 24.04, Debian 12, Fedora and Homebrew. It is deliberate. The right fixes,…
Debugging & Errors
Assignment to Expression with Array Type
Why Python raises "cannot assign to expression here" when you annotate a subscript, and the same-sounding TypeScript and C errors, each with…
Debugging & Errors
Syntax Errors vs Logic Errors vs Runtime Errors
The three kinds of programming error, how to tell them apart from the way they fail, and the different technique each one…
Debugging & Errors
How to Fix “SyntaxError: Cannot use import statement outside a module”
This JavaScript error means the file is being read as a script, not a module. Here are the fixes for Node, the…
Debugging & Errors
Why Is My HTML Not Showing Correctly?
Your page is blank, half-rendered, or nothing like the file you wrote. An ordered checklist from most to least likely cause, with…
Debugging & Errors
VS Code Problems Beginners Hit (and How to Fix Them)
Python not found, the wrong interpreter, imports that fail, a terminal in the wrong folder, Live Server not working. The setup problems…
Debugging & Errors
Why Is My Python Code Not Working?
A triage guide for when your Python program will not run or gives the wrong answer. The eight causes behind most beginner…
Debugging & Errors
How to Debug JavaScript in the Browser
Console logging that actually helps, breakpoints, stepping through code, and the Network tab — the four tools that solve nearly every front-end…
Debugging & Errors
Why Is My CSS Not Working? A Checklist
Your styles are not applying. Work through this ordered checklist — file linking, selector accuracy, specificity, inheritance and cascade order — to…
Debugging & Errors
How to Read a Stack Trace
A stack trace is a list of the function calls that led to an error. Here is how to read one in…
Debugging & Errors
Common JavaScript Errors and What They Mean
The JavaScript console errors beginners see most, what actually causes each one, and how to fix them — including the undefined error…
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Where to go next
Programming Basics
The ideas every language shares — variables, loops, functions and how a program actually runs.
17 guides
Python
Plain-English Python guides, from your first line of code to small programs that do real work.
72 guides
JavaScript
How JavaScript works in the browser, explained with short examples you can paste and run.
32 guides
Keep going — pick your next guide
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