Your learning data.
This notice describes the current HangulHada web preview, operated by 하대환. Updated 21 September 2026.
What is saved
We save lesson identifiers, the section you last used, your selected review answers, most recently checked answers, missed question numbers, best review scores, completion status, review intervals, next review dates and update times. Guest records are linked to a random browser cookie. This is not a name or email address, but it still identifies your guest learning record.
Optional sign-in
ChatGPT sign-in supplies a site-specific user identifier and account information to this site. Our learning database stores the identifier and your learning records, not your email, password or recording. Sign-in is used only to find and sync your progress. Google and Apple sign-in are not connected.
Your voice
The microphone is used only when you choose Record and grant permission. Practice recordings remain in the current page’s memory and are not uploaded by HangulHada. Leaving the page or replacing the recording removes that recording from the page. Listening uses your browser or operating system’s speech service for the language you are learning; some voices use a network service governed by that provider.
Practice room
Freehand drawings, card positions and matched-block counts stay in this page’s memory. They are not uploaded or added to your saved learning record. Changing a writing target clears its drawing; leaving the page clears the practice round. Lesson reviews continue to use the saved progress system described above.
Storage and service providers
The site runs on OpenAI Sites and its Cloudflare hosting infrastructure. Progress is held in the site’s server database. Hosting and sign-in providers process technical information needed to deliver and protect the service, such as network requests. The web preview loads typefaces from Google Fonts, which receives the network requests needed to deliver them. HangulHada has not added advertising or analytics trackers. Data may be processed outside your country.
Your choices
You can download your saved learning records from My progress. Your language and course choice and a selected speech voice are stored only in this browser. Country cards suggest a language; we do not detect or store your location. Public lesson files are cached on the device for offline reading; personalized API responses are not cached by our service worker.
Retention and deletion
Learning records remain until you delete them. Use the deletion page while you still have your guest cookie, or sign in to the same ChatGPT account for synced data. Clearing guest cookies removes your access key but does not itself delete the server record, so delete learning data first if you want it removed. Deleting HangulHada records does not delete your ChatGPT account. Our deletion control removes active learning records from this site’s database; hosting-provider logs and backups follow those providers’ retention practices.
Manage or delete learning data
This web preview
No purchases, subscriptions, public profiles or user messaging are offered. This notice covers the current web preview and will be updated before new account providers, payments, analytics or app-store releases are introduced.