Five little words you do not want to hear: “Your computer has a virus.” Even if you know almost nothing about computers, you know this is bad. So why would anyone create a virus anyway!? Malware, short for malicious software, includes many types of software written with the intent of harming your computer, invading your privacy, stealing assets or passwords for identity theft, or simply to be annoying.

Malware includes viruses, worms, Trojan horses, spyware and more. People might create malware for the purpose of making money, reselling information, playing with a company’s systems or networks, or simply proving that it can be done.

How does malware infect your computer in the first place? A virus or other malware can get to your computer through email attachments, applications you download, and from clicking on links to compromised or malicious websites. Another common way that viruses and malware spread is through USB devices. If your copy info from someone else’s USB thumb drive, you could also “unwittingly” be copying malware onto your computer—you can get infected that way too.

So who creates viruses? Many viruses and other malware are intended to make money either by tricking you into buying and downloading software, or by forcing you to look at ads or web pages. What’s worse, malware can record your keystrokes, capturing information like passwords and credit card numbers, which can give the author access to all kinds of information that you want kept private. Armed with personal information like that, the malware developer could steal your identity, access bank accounts, and open credit cards in your name.

Some malware is created by people who want to damage a company or organization. If a virus can tie up an organization’s network, it can cost them serious amounts of money. This might be created by a disgruntled employee, or someone else with a specific agenda.

There are a few things that we all can do to protect our computers. First, use proactive anti-malware software, such as Trend Micro Maximum Security. It prevents access to infected websites, cleans malware from your email, and blocks infected files from USB devices. Second, never open an attachment from someone that you don’t know. Third, be careful when you’re surfing random websites, particularly if they would not be considered “mainstream.”

If you do get infected, Trend Micro offers free tools to clean up your computer and get you back in the running. In short, whenever you go online use caution and keep your defenses up! Most importantly, use anti-malware software and keep it up-to-date.