What are cookies?

The simple version

A cookie is a tiny piece of text a website asks your browser to store, then sends back to that same website on later visits. That's it — it's not a program, it can't run code on its own, and it can't reach into your files or camera. Think of it like a coat-check ticket: the website hands your browser a small tag, and shows it back the next time you visit so it can say "oh, it's you again" without asking you to re-enter everything.

Why this site uses one

This site remembers two small preferences: whether you prefer dark or light mode, and whether you'd rather have motion/animation on or off. Those are saved in your browser (via localStorage) and mirrored into a small first-party cookie so they hold steady across visits to this site, on this browser. Alongside them, the cookie carries an opaque device ID — a random string with no meaning on its own — so returning visits on this browser can be matched back to those same two preferences.

What this cookie is not

• It doesn't identify you. The device ID is a random value generated in your browser — it isn't your name, email, IP address, or anything tied to who you are.
• It doesn't follow you across browsers. Cookies are stored per-browser, by design. If you visit in Chrome and then Safari, this site sees two separate, unconnected visits — there is no cross-browser or cross-device tracking here, and no fingerprinting technique is used to fake that connection.
• It isn't shared. This cookie is never sent to advertisers, analytics networks, or any third party. It's read only by this site's own front-end code, for the sole purpose of restoring your appearance/motion choice.
• It isn't used for advertising. There are no ad trackers, cross-site pixels, or marketing cookies anywhere on this site.

The technical details

• Name: musa_device_id, musa_theme, musa_motion
• Set by: your own browser, client-side (no server ever writes or reads it)
• Lifetime: up to 1 year, or until you clear your browser's cookies/site data
• Attributes: SameSite=Lax and, on the live site, Secure (HTTPS only) — so it's never sent over an insecure connection or to another site
• Scope: first-party only — sent solely to this site's own domain, never to a third party

The one other cookie on this site is a short-lived, httpOnly login session that's set only in my browser when I sign in to publish a blog post. It never applies to visitors and can't be read by any page script.

Managing or clearing it

You're always in control. Your browser's settings let you view, block, or delete cookies for this (or any) site at any time — doing so simply resets your appearance/motion preference to your system default on your next visit. Nothing else changes.

More detail

For the full picture, including analytics and third-party services, see the Privacy Policy.