Short answer: Tails is a live operating system you start from USB (or DVD). It sends network traffic through Tor by default and, without persistence, leaves little on the computer’s internal disk after shutdown. It does not fix a bad threat model, infected firmware, or a keylogger in the keyboard. Download only from tails.net and verify the image.
Tails (The Amnesic Incognito Live System) sits one layer above Tor Browser: the whole session is a known OS, not a Firefox profile on whatever Windows install you already had. The tool profile is the short card. This guide is the catalog of promises and refusals.
What Tails is for
Sessions that should not write research residue onto the host drive: borrowed hardware, a shared family PC, a role you do not want mixed with a daily login. It is heavier than opening Tor Browser. For everyday browsing with a weaker model, the browser on a current OS is enough. For a persistent workstation that still cannot talk to the net except through Tor, Whonix is the usual comparison — two VMs, not a USB reboot.
Tails does not run on smartphones, tablets, Raspberry Pi, ARM, or Apple-silicon Macs. It wants a 64-bit x86-64 PC, about 3 GB of RAM to stay stable, and the ability to boot from USB. Nvidia and AMD Radeon graphics often fail. Those constraints are from Tails’ own requirements page, not from a market guide.
Amnesia is the default
Without the optional encrypted volume, installed extras, browser state, and documents live in RAM and vanish at shutdown. Tails also documents a RAM wipe on power-off, aimed at cold-boot extraction. That is why checklists talk about a full shutdown, not sleep.
Amnesia does not erase:
- files you saved to another stick or to the host disk by mistake;
- what a site already stored about the account you logged into;
- firmware, BIOS/UEFI, or a hardware implant.
Tails’ own warnings page is blunt: the project is safer than a typical OS for its design, and it is not magic.
Persistence is a trade
An optional encrypted partition on the USB can keep selected data across reboots (keys, bookmarks, documents you choose). Without the passphrase, Tails describes that area as indistinguishable from random data. Convenience rises. So does the value of the stick if it is seized or copied.
Tails recommends treating persistence as something you backup by cloning to a second stick of similar size — not as a cloud sync. A third, cheaper stick appears in their upgrade notes for occasional manual upgrades. Official installers and clone flows live on tails.net; unofficial “Tails with extras” images are phishing. See phishing detection.
If two roles must not share artifacts, Tails’ identity guidance is to restart between purposes, or use a different stick per role. Logging into two accounts on one site in one session lets that site see one Tor circuit serving both. That is not a Tails bug; it is how websites see circuits.
Metadata still travels
Images and office files carry camera models, authors, and timestamps. Tails ships Metadata Cleaner (MAT2) because those fields have identified people from “anonymous” photos. Strip before you share. The same discipline applies on desktop Tor Browser; the live OS just makes the tool available by default.
Tor’s limits are still Tor’s limits
Everything Tails does on the network goes through Tor. Your ISP can see that you are talking to Tor (unless you use a bridge). Destination sites can see an exit or an onion service. Exit relays can observe or tamper with unencrypted clearnet HTTP; HTTPS and onion services are the usual answers.
Tails documents end-to-end correlation as a research-class attack: an observer who sees both ends of a circuit may identify users. No low-latency anonymity network eliminates that class. A VPN is not a stronger answer to it; see Tor vs VPN.
Untrusted computers
Tails can run on a machine whose installed OS is full of malware, because it does not boot that OS. It cannot protect you if:
- you install Tails from that infected OS (the image you wrote may already be wrong);
- you plug the Tails stick into a running untrusted OS to “just copy a file”;
- the firmware or a physical keylogger is already hostile.
Tails’ advice: install from a computer you trust, or clone from someone you trust; keep the stick for Tails rather than as a general USB drive; use a password manager paste or on-screen keyboard if you think the keys are watched. No OS, including Tails, can audit the BIOS for you.
USB hygiene from the same docs: 8 GB minimum; prefer new, known-brand sticks bought locally rather than mystery mailers (BadUSB-class tampering is a documented worry). All data on the target stick is destroyed when you install.
How this sits next to other tools
| Layer | Typical choice | Tails adds |
|---|---|---|
| Browser path | Tor Browser | Same Tor path, plus OS amnesia |
| Isolation without reboot | Whonix VMs | Opposite trade: persistence on the host hypervisor |
| Phone | Tor on mobile | Nothing — Tails is not a phone OS |
| Signed image | torproject.org / tails.net | You still verify; see PGP |
TorWiki’s access and privacy-tool pages call Tails a default for “high” models and mention persistence for keys. That matches Tails’ own product shape. It does not mean every catalog reader needs a USB ritual, and it is not a buying guide for markets.
What this guide will not do
We will not paste a BIOS key sequence for every laptop, rank USB brands as a shop, or tell you which persistence features to enable for a marketplace account. Follow Tails installation for the current wizard. Pair practice with OPSEC so the live system is not covering for a reused pseudonym.
Sources
- Tails: Warnings — Tails is safe but not magic
- Tails: System requirements and USB sticks
- Tails: Install
- Tor Project: Tails as a documented high-isolation option in project materials
- TorWiki: Tails in access / privacy-tool overviews (paraphrased)
- Electronic Frontier Foundation: Surveillance Self-Defense