Be secure online

When you use the internet, you may be connected to thousands of other computers that you exchange information and data with, including personal details. It is important to make sure your device, your information and your privacy are as secure as possible. Some simple precautions will keep you safe online.

How your computer could be at risk

Most people store a lot of personal information on their computers. If you don’t protect your computer properly when you're online, it’s possible that personal details could be stolen or deleted without your knowledge.

Your computer can be attacked in a number of ways over the internet. Viruses and spy-ware can remove files and allow criminals to scan your computer for personal information. Your computer could even be hacked (when a person gains access to your computer through your wireless network).

Get Safe Online has detailed information about the risks to your computer and how to deal with them.

Being aware of the risks

Malicious Software (known as 'malware')

Malware is short for malicious software. Detailed below are different kinds of malware that are a risk to computer users in everyday life, for example Spyware, Ransomware and so on.


A piece of software that allows a criminal to spy on a user (without their knowledge) when they are using their computer. These spying capabilities include actively monitoring a user and collecting what a user is typing including collecting bank details and passwords.

Spyware software can be downloaded with other software, like music sharing software.


Ransomware is a form of malware (malicious software) that gives criminals the ability to lock a computer from a remote location, which means that the computer owner can't use their computer.

The criminal will then send a message to the owner's computer saying that the computer will not be unlocked until a sum of money is paid. In some cases, the only usable part of the computer is the number keypad to enter a PIN to allow payment to the criminals. 

If your computer has been locked by ransomware, get professional advice from a trustworthy source.


A Trojan is a type of malware that disguises itself as a normal file or computer program to trick users into downloading and installing malware on their computer. 

A Trojan can give a criminal remote access to an infected computer. Once an attacker has access to an infected computer, it is possible for the attacker to steal information like login details, banking information or even electronic money. The attacker can also use the Trojan to install more malware to change files and monitor user activity. 


Viruses are destructive software that can run on your computer without you knowing. They spread through the internet and emails by copying themselves to documents and programmes on your computer. Viruses can cause damage by deleting files and can allow criminals to monitor your computer and steal personal information. They can slow down your computer and take days to remove.


A botnet is a network of virus-infected computers that are used together and can be remotely controlled. The attacker can then have access to the computers and use them for malicious activities, such as sending spam. All this can be done without the computer users knowing what is happening.

Common signs that your computer has been attacked

Even though there are a wide range of malware types, the majority of them produce similar symptoms. Below are the more common symptoms:

  • your files being edited or deleted without your permission
  • your computer freezing or crashing more than normal
  • strange files appearing on you computer that you haven’t downloaded 
  • emails or messages being sent out from your email or social media without you knowing
  • increased CPU usage - central processing unit (CPU) carries out the active tasks and processes that are running on your computer - malware makes your computer work harder than normal and your CPU usage will show this
  • general strange behaviour from your computer

Security measures you can take

Using the most up-to-date version of your operating system

Your operating system is the main piece of software controlling your computer. The most common systems are Microsoft Windows (used on PCs), Macintosh OS (used on Macs) and Linux (used on Linux computers).

All new computers have this software installed. The most recent version of the software is usually the most secure. Updates are usually available from the software manufacturer and are free to download.

Make sure you have a desktop firewall in place

A firewall is software or hardware that acts as a filter between your computer or network and the internet. Using a firewall prevents unauthorised access to your computer and is designed to stop worms (another type of malicious software).

Desktop firewalls for individual computers are available in high street shops. Some operating systems have built-in firewalls but it's best to check with the manufacturer and find out if it provides adequate protection.

Using up-to-date antivirus software

Antivirus software checks your computer for viruses and alerts you about those it recognises. It's important to keep this software up-to-date, as new viruses are being created all the time.

Use strong passwords

Many websites use passwords to protect your identity. If your passwords are easy to guess, someone else could work out what they are. Using strong passwords is especially important when you're spending money online. Good passwords should:

  • never be shared or written down somewhere  - don't tell helpline staff your password
  • the longer the password, the harder it is to crack - so aim for a password with a minimum of eight characters
  • include lower and upper case letters, numbers and other keyboard characters
  • change regularly - every three months is a good guide
  • not be the same on all the websites you use
  • don't use obvious passwords like “password” or “1234567” - a hacker can guess these in seconds and should be avoided at all costs

These guidelines make it more difficult for hackers to crack your password therefore use unusual passwords.

Log off and collect print-outs

If you’re accessing a site where you have provided personal details or a password, always log off and close your browser window when you've finished. This is especially important if you are using a shared computer, for example, in an internet café or library.

Make sure you collect anything you print from the printer or your personal details might fall into the wrong hands.

Monitoring your family's use of the internet

Make sure everyone's aware of internet safety issues, especially young people who may use file-sharing programmes, instant messaging and chatrooms more than adults. Think about restricting sites they can view and what they can download. It's usually possible do this through the settings on your browser or you can buy separate software.

Online scams

A scam is an illegal scheme that tries to trick you out of your money. Online scams use the internet and email.

Find out more about online scams:

scamwiseni provides information on:

  • the latest news about recent scams
  • how to recognise a scam 
  • how to beat the scammers 
  • who to contact if you think you have encountered a scam
  • how to protect yourself from fraudsters in 'The Little Book of Big Scams' 

Shopping safely online

There are a few steps you can take to shop online safely and keep your financial details secure.

Before you buy

Before you buy online, note the address, telephone number and any other contact details of the company you’re buying from. Never rely on just an email address.

Always use secure sites

Sites with 'https' in front of the web address mean the company has been independently checked to make sure it is genuine. A yellow padlock symbol will appear in the browser window to show the payment process is secure.

When buying online:

  • never transfer or receive money for someone else
  • check the site's privacy and returns policy
  • print a copy of your order and any acknowledgement you receive
  • check your bank statement carefully against anything you buy online
  • keep your passwords secure
  • take your time making decisions that involve parting with money
  • get independent financial advice before making investments
  • only do business with companies you recognise or have been recommended by someone you trust - don't judge a company on how professional their website looks
  • if in doubt, check a company is genuine by looking them up on Companies House website or the Financial Services Register
  • find out about your rights when shopping online Online shopping

Other ways to stay secure

  • avoid disclosing personal information as much as possible
  • never give your passwords, PIN numbers or bank account numbers to anyone
  • only open email attachments from people you know
  • be careful about sharing files and downloading software, as these can easily spread viruses and hide spy-ware
  • never download pirated software, music or videos
  • for email, turn off the option to automatically download attachments
  • be suspicious of unknown links or requests sent through email or text message - don't click on unknown links or answer strange questions sent to your mobile device, regardless of who the sender appears to be

If you'd like to have a printed version of 'Be secure online' tips, you can download the following brochure: 

How to report incidents of cybercrime 

  • if you have been the victim of cybercrime - contact Action Fraud

For more information on how the Police Service of Northern Ireland (PSNI) deal with cybercrime, visit 'What is Cyber Crime?' 

More useful links

Share this page


Your comments are anonymous and can’t be responded to - if you would like a reply, use the feedback form.

Your comments
Plain text only, 750 characters maximum. Don't include personal or financial information.