Princeton Labs
Privacy policy
Last updated October 25, 2026
- There are no accounts, no sign-ups, no ads and no cookies.
- Your progress is saved only in your own browser. It is never sent to me.
- Nothing is counted or tracked. There are no analytics on these sites.
- I don't sell, rent or share data with anyone.
This policy covers Princeton Labs (jiacode2030.github.io/princeton-labs/) and its course sites: PHY 103 Lab (jiacode2030.github.io/phy103-lab/) Multivariable Calculus Lab (jiacode2030.github.io/multivariable-calculus/) and COS 126 Lab (jiacode2030.github.io/cos126-lab/). They are free study sites made by Jiarui Li, a student.
1. What stays on your device
The sites save your study progress in your browser's local storage, so it is still there next time. This data stays on your device. It is never sent to me or anyone else.
| Site | Keys start with | What is saved |
|---|---|---|
| PHY 103 Lab | phy- | Modules marked done, solved practice problems and your review queue |
| Multivariable Calculus Lab | mvc- | Which lessons you have visited |
| COS 126 Lab | cos- | Modules marked done |
| Princeton Labs (this page) | nothing | Nothing is saved. The landing page only reads the course keys above to show your progress, and never changes or sends them. |
To delete it, clear this site's data in your browser settings. Using a private window means nothing is kept after you close it.
2. No analytics
These sites don't use any analytics, counters, trackers or advertising. I don't know who visits or what they do on the sites.
3. Services that deliver the pages
Like any website, these pages are delivered by other companies. Your browser connects to them, which shares your IP address and basic browser details with them:
- GitHub Pages hosts the sites. See the GitHub Privacy Statement.
- Google Fonts provides the typefaces. See Google Fonts privacy.
4. Reporting an error
The "Report" links on the course sites open a pre-filled form on GitHub, in that site's public repository. Nothing is sent until you press submit there. You need a GitHub account, and your report and username are public. Please don't include your real name, NetID, email or anything else personal.
5. Links to other sites
The sites link to other websites, such as GitHub. Those sites have their own privacy policies, which apply once you visit them.
6. Your choices
- Clear your browser's site data at any time to delete your saved progress.
- Ask me to delete a report you filed, or anything else, using the contact options below.
7. Changes
If this policy changes, I'll update this page and the "Last updated" date at the top.
8. Contact
Open an issue in the PHY 103 Lab or Multivariable Calculus Lab repository. For COS 126 Lab, use the COS 126 Lab repository.