What is Malware? Part I

You’ve probably heard the term Malware before.  However, many people are confused as to what malware is exactly.  Many people will exclusively use the term virus, but that is just one type of malware. Malware is short for “Malicious software”.  It’s an extremely broad definition that is meant to encompass all things from viruses, to spyware, to worms, and beyond.

What are all the types of malware? In this two part article, we will explain the different types of malware and how you can best protect yourself against them.

Types of Malware

Malware comes in many different shapes and sizes. Here is a list of the most abundant forms of malware out there.


Probably the most common form of malware is a virus. Viruses work in computers almost the same as they do in humans.  It copies itself by infecting other files on your computer.  Viruses can have many different effects. Viruses can show you popup ads, steal information from your computer, or completely crash the system.

The way you technically define a virus is by how it spreads.  Once the virus has been clicked, it will begin to infect other files/programs on the computer.  For instance, if you get an email and open an attachment that is infected, it will begin to spread on your computer.  This happens many times over and over again as the virus fools many people into clicking on the attachment. The virus will continue to spread as long as it is clicked.


Computer viruses act very much like biological viruses.

Trojan Horse

A Trojan horse, also referred to by just Trojan, is designed exactly as the Greeks used it during the Trojan War.  This type of malware disguises itself as a legitimate file or program and fools the user into downloading it.

Trojans have many different targets once they infect your computer.  Specific Trojans will do many different things such as quietly sit in the background collecting information, or giving a 3rd party access to your machine.

The method of transmission is what sets Trojans apart from other malware. Trojans can be very dangerous since they trick the user into believing what they are downloading is a legitimate program. Trojans don’t need to spread like viruses and worms typically do.


Trojan horse malware disguises itself as legitimate software.


Worms are one of the most dangerous type of malware on a PC.  Worms behave very much like viruses, however instead of requiring the user to click and run the virus to spread it, a worm can spread entirely on its own over the network.

Worms usually access systems through a vulnerability in a program or operating system.  Generally, you see this on older unsupported systems, or PCs that have failed to maintain proper security patching.  Worms these days are typically blocked by common firewalls that come preinstalled with your operating system.  However, just like viruses, a typical spreading technique of worms is through emailing.  It only takes one person to be infected then the worm will mass email itself to everyone in their address book and the plague continues.


Worms dig through a computers files without any user interaction.


These two types of malware typically go hand in hand. These types of malware invade your privacy and are usually more annoying than anything else.  Let’s talk about adware first.

Adware is software that will display advertisements to you…usually in bulk.  Mass amounts of popup ads are a good indication of an adware infection. Some adware will display advertisements when you’re not even browsing the internet. Sometimes it will inject an ad when you’re not even doing anything.  Other types of adware will insert more ads into the web pages you browse. Adware and spyware work in tandem to target specific ads to you, with regards to what you’ve been looking at online.

Now let’s discuss spyware.  Spyware gets its name because it spies on you without your knowledge.  It sits in the background collecting different types of data depending on what it’s looking for.  It could be financial information, passwords, or browsing habits.

The problem with these two types of malware is that the ones that only collect “browsing habits” are considered more socially acceptable and are often times bundled with other legitimate software.  The creators of these programs then profit by selling your information off to 3rd parties.  To us at Elkhorn Computer, that’s an invasion of privacy and should not be something that is so easily packaged with other legitimate programs.


Spyware collects data in the background while adware injects annoying pop up ads.

How can I protect myself?

There are several lines of defense when it comes to malware.

We recommend always using an anti-virus for starters.  You can also use an anti-malware program that is more specialized in catching other types of malware. ALWAYS keep up-to-date on system and software updates.  In windows you can run the windows update utility to make sure you have the latest patches from Microsoft.  They release these updates to fix bugs and/or patch security flaws that have been discovered.  If you’re still using an older unsupported operating system (such as XP or Vista) it’s time to upgrade to Windows 10.

Part II coming soon!

We covered some very common and dangerous malware in Part I of this article. Make sure to check out Part II where we discuss malware such as rootkits, botnets, keyloggers, and Ransomware.

If you’re looking for the best computer repair in Omaha, look no further than Elkhorn Computer. Take our customers word for it – we’ve been voted first place in the Best of Omaha Computer Repair for 2 years running! Business or residential, when it comes to computers, we’ve got you covered.