Comments and error messages

Two skills separate people who stick with programming from people who quit in week one: writing notes to your future self, and staying calm when the computer complains. Let's build both.

Comments: notes Python ignores

Anything after a # on a line is a comment — Python skips it entirely. Comments exist for humans:

Three everyday uses:

1. Explaining why — # freeze one day per week so streaks survive rest days
2. Temporarily disabling code — put # in front of a line to "switch it off"
3. Leaving TODO markers — # TODO: handle negative numbers

Your first error message

Run this — it's broken on purpose:

You'll get a SyntaxError — Python's way of saying "I couldn't even understand this as Python." Here it means a ) is missing. Add it and run again.

Reading a traceback

Now a different kind of error:

This is a NameError: the code is valid Python, but mesage doesn't exist (we never created it — and we probably meant something spelled differently). Error messages follow a pattern:

Part	What it tells you
Error type (NameError)	The category of problem
The message	What exactly went wrong
The line number	Where to look

That's not the computer scolding you. It's the computer filing a very precise bug report, for free, in milliseconds. Experienced programmers see error messages all day long — the skill isn't avoiding them, it's reading them.

Camp 1 complete! 🏕️

You know what programming is, you've written real programs, and you can read error messages. That's the whole first camp. Next up: variables — teaching Python to remember things.