Online notepad
Just write: every change saves itself in your browser. Close the page, come back tomorrow, and everything is right where you left it.
How autosave works
Every keystroke writes your text to localStorage, the small local store your browser reserves for this site: there's no "Save" button to remember and no account to create. Reopen the page — even after restarting your computer — and the text reappears exactly as you left it. Two things to watch out for: private/incognito mode keeps nothing once the window closes, and clearing your browsing data wipes the notes too. Notes also don't sync between devices: they stay on the browser where you wrote them.
When to download the .txt file
The download button creates a plain text file straight from your browser, with no server involved. It's the right way to back up important notes, move them to another device, or paste them into a document: the .txt format opens anywhere — Windows, Mac, or phone — and never gets corrupted. A good habit: download a copy before cleaning up your browser, or whenever your notes turn into something you can't afford to lose.