Using a library or shared computer safely.

Why a shared computer is different

Other people use it after you. What you leave on it, they may see.

Libraries, community centers and offices often have computers anyone can use. They are a good way to get online. The difference is what stays behind: a password the browser saved, an account still signed in, a file in the downloads folder, a page in the history. The habits below come from government cyber security and consumer agencies.

None of this is about any particular library or product. If you’re not sure how a computer works, ask the staff.

Private windows, and what they don’t do

A private window helps with history. It doesn’t make you invisible.

• What it does. The Scottish Government’s mygov.scot explains that if you browse in a private window, no search history is saved after you close the browser. Every major browser has one, under a name such as private window, private browsing or incognito.
• What it doesn’t do. mygov.scot warns that anything you download and save is not private, and that if you don’t close the private window, the next person can use the back arrow to see the sites you visited.
• Close it when you finish. Closing the whole private window is the step that clears it.

Don’t let the browser save your password

On a shared computer, say no when it offers.

• The UK National Cyber Security Centre (NCSC) is clear: on a shared device outside your home, such as a desktop computer at a college, library or other public place, you should never save your password in the browser.
• At home it is different. The NCSC says saving passwords in the browser is safe on your own devices. On a device shared within a household, it says to think about who else could get into your accounts, and if you aren’t sure, not to let the browser save them.
• Watch for “shoulder surfers”. Get Cyber Safe, from the Government of Canada, says to keep an eye out for anyone who might be watching your screen over your shoulder in a public place. That includes when you type a password.

Two-step codes on a shared computer

Expect to be asked for a code, and keep it to yourself.

• Why you may be asked. The NCSC explains that with 2-step verification you may only need to enter a code when something looks unusual, such as a sign-in from a different device. A library computer is a different device, so expect a code by text, email or an app.
• Bring what you need. Get Cyber Safe describes one of the factors as something you have, such as your phone. If your codes go to your phone, have it with you before you sit down.
• A code is like a key. Never give a one-time code to anyone who contacts you, even if they say they are from your bank or a government agency. Signing in yourself is the only reason to type one.

Downloads and printing

Files can outlast your visit.

• Downloads stay. mygov.scot warns that anything you download and save is not private, even in a private window. Where you can, save to your own device or account rather than to the computer, and delete anything you downloaded before you leave.
• Printing. None of the official pages we opened covers shared printers. Collect everything you printed before you leave, and if a print doesn’t appear, ask staff rather than sending it again.

Public Wi-Fi

Official sources don’t all say the same thing. Here are both views.

• The FTC (US) says most websites now use encryption, so connecting through a public Wi-Fi network is usually safe. Look for a lock symbol or “https” in the address bar. It adds that scammers can make fake sites look encrypted too, so the lock alone doesn’t prove a site is genuine.
• Get Cyber Safe (Canada) is more cautious. It says anyone can connect to public Wi-Fi, including criminals, warns about fake hotspots, and says never to use public Wi-Fi for sensitive information like your bank account or a purchase. It suggests turning Wi-Fi off when you don’t need it.
• What both say. Check the address of the site you’re on, and look for the lock. If you’re unsure, wait until you’re on a connection you trust.

When you finish

Two minutes before you stand up.

1. Sign out of every account. mygov.scot notes that if you stay signed in to an account on a browser, the next person may see your recent searches, and if you stay signed in on a device someone else can access, they may be able to see where you are through location apps. Signing out stops that.

2. Close every browser window. Including any private window, so the back arrow shows nothing.

3. Delete what you downloaded, and take your printouts with you.

If you forgot to sign out

It happens. These steps come from the NCSC’s guide to recovering an account.

1. Change the password, from a device you trust, for the account you left open, and for any other account that uses the same password. The NCSC says both matter, because criminals try the same password on other accounts.

2. Sign out everywhere. The NCSC says most services let you log all devices and apps out of your account, usually from the Settings, Privacy or Account options. After that, anyone trying to use your account is asked for the new password.

3. Turn on 2-step verification if it isn’t on already. The NCSC calls it one of the most effective ways to protect your accounts.

4. Check for anything you don’t recognize, such as messages you didn’t send or changes to your settings, which the NCSC lists as signs of a hacked account.

If you think someone has already used your account, or you clicked a link you shouldn’t have, After a phishing click explains the next steps, and free help by country lists official places to report it.

For library and front-desk staff

Points to share with people using the computers. How the machines are reset between users is a question for your IT help.

• Remind people not to let the browser save passwords: the NCSC says never to on a shared computer at a library.
• Suggest a private window, and explain that downloads stay on the computer and that the window only clears when it is closed (mygov.scot).
• Before a banking or health portal session, remind people to bring the phone their sign-in codes go to (NCSC, Get Cyber Safe).
• Leave space between screens where you can; Get Cyber Safe warns about people watching screens in public places.
• Keep the checklist below by each computer. It prints on one page.

A one-page checklist

Print it for each computer, or keep it on your phone.