What is Malware?

Malware is short for ‘malicious software’. Cyber criminals use malware to make your computer malfunction, cause damage, disrupt you or steal your information for financial gain. Your computer can become infected with malware in many ways; when you download software, share files, click on links on emails, or insert USB drives, to name a few.

Common types of malware are:

  • Keylogger – this monitors everything you type on your keyboard in order to steal passwords or credit card details.
  • Spyware – this is a program designed to secretly allow someone to spy on what you do on your computer.
  • Trojan – this let criminals access your systems and information without your knowledge.
  • Ransomware – this locks all your files and then asks you to pay a ransom to unlock them.

How can I tell if I'm a victim of malware?

Some of the signs your computer is infected with malware are:

  • It takes longer than normal to start and is running slowly
  • New and unfamiliar icons appear on your desktop or browser
  • It keeps crashing.

Keep in mind some types of malware especially, keyloggers and Trojans, are very difficult to identify.

How can you help protect your business from Malware?

  • Keep your software up to date. Malware is always changing. Criminals get smarter and more innovative every day, so ensure you set automatic software updates.
  • Use anti-virus software. Install a reputable anti-virus program and keep it up to date. Never rely on trial version, because they quickly go out of date.
  • Create backups. Put in place procedures to regularly (or automatically) backup (copy) your important files. You should do this on a separate device to your computer, such as a USB memory stick, portable hard drive or CD, or secure cloud-based storage.
  • Educate your employees to recognise suspicious messages. Criminals often send malware in the disguise of links or attachments in emails or text messages.


Susan’s computer is running slow and some of her files are missing. She recently received an email from a supplier she knows, which asked her to urgently open a document. Although she didn’t recognise the name of the sender, the email address looked fine and she opened the document but it was blank. Could Susan’s computer contain malicious software?