What is malware?

"Malware" is a contraction of the words malicious and software. It covers all forms of harmful software designed to damage, spy, steal or exploit your computer, phone or data.

It can be anything from an annoying ad program to a malicious program that encrypts all your files and demands money to unlock them. Malware can be hard to detect, and it can hit anyone, both individuals and businesses.

How does malware get in?

Malware often spreads without you noticing. Here are some of the most common ways it happens:

You click a link in a phishing email.
You download a free file or program that contains hidden malware.
You visit a fake or compromised website that automatically installs malicious code.
You plug in a USB stick that's already infected.
You open an attachment from an unknown or “suspiciously familiar” sender.

Many forms of malware try to stay invisible. They install themselves in the background and wait for you to type passwords, log into your netbank or use your webcam.

What types of malware exist?

There are many kinds of malware – and new types appear all the time. Here are some of the most common:

Virus – spreads to other files and programs.
Trojan – pretends to be something useful but contains malicious code.
Spyware – monitors you and sends information onward.
Adware – shows annoying ads and tracks your behavior.
Ransomware – locks your files and demands payment to get them back.
Keyloggers – record everything you type, including passwords and messages.
Rootkits – hide deep in the system and can be almost impossible to remove.

Some types of malware combine several functions and can be extremely advanced.

What can malware do?

Malware can be much more than just annoying. It can lead to:

Theft of your passwords, card details or identity
Loss of important files and photos
Financial losses, e.g. if you pay to get your files back
Surveillance of your activities without you knowing
Spreading to others – malware can use your computer to infect friends and colleagues
Performance issues where your computer becomes slow and unstable

It's not only you who can be hit – malware often uses your systems as a springboard for larger attacks.

How do you detect malware?

It's not always easy to detect malware – but some signs can be:

Your computer suddenly becomes slow
Programs freeze or close unexpectedly
You see strange ads, even when you're not online
Programs are installed that you didn't choose yourself
Your internet connection is very active, even when you're not using it
You're asked to pay to access your own files

If you experience something unusual, it's better to react once too often than once too little.

How to protect yourself against malware

Here are some good tips to avoid malware in everyday life:

Never click on links or attachments unless you're absolutely sure they're genuine.
Keep your operating system and programs updated – it closes security holes.
Use a reliable antivirus program and let it run in the background.
Never use pirated programs or “free” software from unknown sources.
Be skeptical of pop-up ads and fake “update” messages.
Back up your data regularly, so you don't lose everything if you get hit.
Enable two-factor authentication wherever possible (learn more).

Malware often exploits our busyness and inattention – therefore critical thinking and healthy habits are the best defense.

Malware isn't just something that happens to others

Anyone can be hit – and it's not a question of how technically skilled you are. Many are fooled by messages that look completely genuine, or programs that promise something free and smart.

But you can protect yourself. By understanding what malware is, how it spreads and how to avoid it, you can take care of yourself, your data and your devices.

You don't have to be an expert – just be attentive.