What is Malware? The 5 Types You Need to Know

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What is malware?

By definition malware is an abbreviation of the words “malicious software“. It is a general term used to classify files or software which cause damage to devices and their users. This damage can come in many forms, often involving stealing data from a user’s computer, encrypting this data, or simply deleting it. 

Key takeaway: Malware is software designed to cause harm to you or your devices. It includes many types of programs, such as spyware, ransomware, trojan horses, rootkits and more. They can spread manually or automatically. And range from being a mere inconvenience, to being incredibly destructive. 

Tip: Don’t get infected by malware. Buy anti-malware software.

What is Malware? Types & Examples

What malware types exist?

Depending on the intention of its creator, malware can range from being very sophisticated software, capable of a number of functions to simply being something of a nuisance. There are many types of malware, which differ based on their features or mode of operation. Some of these include:

Computer Virus: A computer virus is the classic form of malware. It is a piece of code or program that makes its way unto your device without you knowing about it. Once there it can cause a range of damages, from slowing your system down, disabling specific parts or taking over entirely. Just like to biological virus, it is designed to keep spreading automatically accross networks and devices.

Spyware: These are malware designed to gather data from a computer and its users. It does this by infiltrating the user’s computer and monitoring their activities. It is installed on the user’s computer directly or by exploiting holes in the cybersecurity.

Ransomware: Much like the name suggests, ransomware is software created for the purpose of ransoming data on the user’s computer. The software is designed to encrypt targeted, sensitive data. The creators then demand money from the user to decrypt the data.

Trojan Horse: This is a type of malware created to appear like a normal program. So much so, that it convinces unwitting users to install it on their computers. Once installed and executed, the Trojan horse can begin performing the malicious function it was initially created for. Unlike viruses and worms, Trojan horse’s rarely try to replicate and spread themselves.

Rootkit: This type of malware is created to grant cybercriminals administrator-level clearance on a target’s computer. This access enables them to modify the user’s computer system. Additionally, it is used to hide the presence of other malware within this computer system.

Backdoor Virus: This type of malware creates a ‘backdoor’ within a target’s computer. Through this backdoor, cybercriminals are able to access a computer without the knowledge of the user. Backdoors are created by other forms of malware, such as worms or Trojan horses. Using a backdoor, cybercriminals also evade the computer’s security programs. One type of backdoor virus is a Remote Access Trojan (RAT).

By clicking on the links in the right side-bar of this article, you can read about many more types of malware.

How to remove malware?

The best way to remove malware is by installing one of the top antivirus software (like Norton, BitDefender, Intego or Panda). These tools scan your system, detect the malware and then delete it. All fully automatic. On top of that, they prevent future malware from being installed on your device.

Of course, there are a few dedicated anti-malware tools you can download for free, but these are not a full solution. They are often focused on removing malware that is already installed on your device, rather than preventing new malware from being installed. They curve the infection, rather than prevent it.

The antivirus software in our comparison not only include anti-malware, but also a range of other features that keep you safe both online and offline. Examples are firewalls, spam filters, parental controls, hardened browsers for online payments, password managers, online backup, website advisors and many more.

What is the history of malware?

One of the earliest forms of malware was the Creeper virus. Created by BBN Technologies engineer Robert Thomas in 1971, it was made as an experiment to infect mainframes of the time with ARPANET. It was not created with any malicious intent, nor was it programmed to steal or encrypt data. It simply moved between mainframes and displayed the message, “I’m the creeper: Catch me if you can.”

The initial version did not self-replicate, but this feature was later added by Ray Tomlinson, making ‘The Creeper’ the very first worm. Malware then began appearing within the tech industry; the 1980s saw the creation of various worms and viruses that infected personal computers. As there was no internet at this time, infection was mainly transferred via floppy disks. These viruses were first created for the Apple II and Macintosh computers; then the IBM PC and MS-DOS when they became more popular. The internet led to an even wider boom in the creation and spread of malware, which could now be found in websites and downloadable internet files.

How does malware work?

The spread of malware largely depends on the intent of the creator. For many viruses and worms, the spread is carried out with the intention of reaching as many computers as possible. As such, the infection occurs when data is shared. This could happen over the internet with downloaded files, email attachments, malicious links or via drive-by downloads, completed without the user’s knowledge.

It also happens when people share files offline with infected computer systems or when sharing certain media. More personal infections are sometimes carried out by physically using USB drives that carry the malware. This is often the case when installing backdoors and rootkits that allow the creators remote or administrator access to the victim’s computer.

Advancements in cybersecurity are often matched with advancements in malware. These new strains are programmed with more sophisticated techniques for evading detection from antimalware programs and computer users alike. These techniques range from simple tactics, such as the use of web proxies (to hide the IP addresses of the creators) to the more sophisticated file-less malware. In the latter case, the malware avoids detection by hiding within the system’s RAM. Malware also takes advantage of vulnerabilities in computer security. They do this by exploiting similarities in operating systems to infect multiple systems. Alternatively, they exploit defects in security software.

What are similar programs?

There are other forms of software which sometimes act in similar ways to malware, but are not strictly considered to be malware. The distinction is based on the fact that while these sometimes cause harm to the user’s computer, they were not created with any malicious intent.

One such program is adware. The most likely impact of these are the endless and annoying ads they spawn. This sometimes negatively affects the performance of a computer. However, adware has been known to be bundled with actual malware. There are also situations where regular software causes unintentional harm to the user’s computer due to malfunctions. This happens because of errors in their code; this type of software is labeled as bugs.


    Tibor Moes

    Tibor Moes

    Founder of SoftwareLab

    Welcome. We started SoftwareLab in 2014 to help you find the best software at the best price.

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