What is a computer virus

A computer virus is a type of malicious software, or malware, that can replicate itself and spread to other computers, often causing damage to data and software. It’s designed to disrupt systems, cause operational issues, and potentially lead to data loss. Viruses work by attaching themselves to other programs or files and then replicating when those infected files are executed. Viruses attach themselves to other programs or files, often disguising themselves as legitimate software or documents. Once activated, viruses can perform various malicious actions, including corrupting data, deleting files, slowing down performance, or even taking control of the computer.

The term “virus” is widely used in everyday language to describe all forms of malicious software (malware), including worms, trojans, ransomware, and spyware. This broad, informal use of the word “virus” has led to the technical definition becoming blurred for many people. What some people would refer to as viruses would be technically worms or trojans or spyware. I’ll try to define the differences in simple words below.

Malware

An umbrella term for any malicious software designed to harm a device, steal data, or hijack systems. It includes viruses, worms, spyware, adware, and ransomware. This term is the correct term to use. When people think viruses in their minds, they are thinking of malware.

Virus

Malicious code that attaches itself to a legitimate file or program and spreads when that file/program runs, often via email attachments or shared files. This term was borrowed directly from biology where viruses are parasitic organisms that attach themselves to host cells and they themselves have no way to reproduce independently.

Worm

A standalone malicious program that self-replicates and spreads across networks without any action from the user, often causing slowdowns or opening doors for other attacks. Worms are bad news. When I have time, I will explain how a worm called Stuxnet was mainly targeted at the centrifuges of Iran’s uranium enrichment facilities, with the intention of covertly derailing Iran’s then-emerging nuclear program and depended on propagating through networks across the world, until it got into Iran’s nuclear facilities.

Spyware

Software that secretly watches what you do—collecting data like keystrokes, logins, or browsing habits—and sends it to someone else without your consent.

Adware

Software that pushes unwanted ads, pop-ups, or redirects. It may track your browsing to target ads; not always outright destructive, but intrusive and sometimes risky as it might redirect you to questionable websites.

Ransomware

Malicious software that locks or encrypts your files and demands payment to restore access. Paying isn’t guaranteed to fix the problem.

Wait.. this is not how viruses in movies 🤔

Aha, Hollywood and their concept of viruses make this topic even more muddled in people’s minds. In movies, someone usually types furiously on a keyboard, plants some virus on a target’s computer, and then infects the target’s whole network. Next thing all screens have been hacked and they are displaying the same thing across hundreds of computer screens. But what did the attacker use? Did they just plant a virus? Or did they infiltrate the network using malware? As you’d obviously know, movies are about suspense and excitement and drama, and they tend to pull the truth a bit (by a bit I mean like a whole lot). In reality, hacking networks through viruses, or malware is a painstakingly slow process. It’s usually something that cannot be rushed and would need hours to explain how it worked. Eg explaining the exploit that the virus or malware used to manage to get access. But that would take too long and is not fun to watch. So, they fudge everything and make it seem like what it’s not in real life.

Despite the widespread image of sophisticated hackers, the reality of cybercrime is often slower and less dramatic.

What’s the Real Threat?

Viruses (malware) in their different forms pose a real threat. And no, they will not hack your screen to display funny sounds and weird graphics. Viruses depending on the purposes of their creation do different things on a computer system all usually deemed harmful. They all disrupt computer systems in some form or another or steal data in some way. Let’s look at some of the type of viruses and the real threats they possess.

• Sudden slowdowns or sluggishness & app crashes, app taking time to open, apps freeze, overworked fans, battery draining faster than normal
• Pop-ups and fake alerts: ads or “Your PC is infected—click to fix!” messages, even when no browser is open.
• Browser hijinks (browser hijacking): homepage/search changes on its own, new toolbars, constant redirects, blocked security sites and potentially being redirected to websites that benefit from your traffic by earning ad revenue. Some of these websites can also be malicious.
• Mystery apps/files: programs you don’t remember installing suddenly appearing with icons on your desktop, new icons, files missing or renamed without your knowledge.
• Account weirdness: friends get strange emails/DMs from you; unexpected login or password-reset notices.
• Security turned off: antivirus/firewall mysteriously disabled without your permission and updates failing repeatedly.
• Network spikes: data usage shoots up; things feel sluggish online without a clear reason.
• Ransom notes: Files won’t open and a message demands payment (ransomware)

How do I protect myself?

There are many ways to protect yourself when using your laptops and mobile devices. The most appropriate thing to do is use antivirus software on your computers. Antivirus software, also known as anti-malware, is a computer program designed to prevent, detect, and remove malicious software from your devices. While the name “antivirus” comes from its original purpose of fighting computer viruses, modern antivirus software protects against a much wider range of threats including the ones mentioned above. In addition to having antivirus software installed, make sure that they are up to date. Most antivirus apps are already setup to automatically keep themselves up to date. This process ensures that they get to detect new viruses and malware as they are being introduced even in the absence of malware definitions describing the malware.

Personally, I use Eset Internet Security which an antivirus application with additional features and functionality that protects one from sophisticated online threats. Other common antiviruses one can purchase online and come highly recommended include Bitdefender, Norton, McAfee, Avast, Malwarebytes, Microsoft Defender, AVG, Kaspersky, and Trend Micro.

In addition to this, keep your software updated. When the operating system lets you know there’s a new update install them to keep your machine safe. Some updates from operating system vendors often patch security holes that viruses exploit. Most of the time, these updates are already setup and should be running.

Also, exercise caution and be smart online. Always assume that someone is out to get you, be sceptical and be on your toes. Be cautious about clicking on strange links, opening email attachments from unknown senders, and downloading software from untrusted sources. This applies more so for your mobile phones. Download apps from legitimate app stores like the Apple App Store or Google Play store and never accept any request from anyone to install apps sent via email or via social media or WhatsApp. Never allow anyone to convince you to change your phone’s settings that prevent installation of apps from unknown sources.

One last thing to keep yourself safe is to back up your data. Always have copies for all your critical and key data on your laptop including settings and files. Some malware are designed to wipe data from a user’s computer and without a computer, a user can lose everything. Microsoft through their OneDrive allows one to back up all the files on one’s computer to the cloud in case anything happens to their machine. Apple through iCloud offers the same services for their Apple devices. Google also offers Google Drive for the same purposes as well. Choose which ever option works for you. I’ll write up another article that compares these backup service providers and what might work for you.

For now, this is all, hopefully you have a better understanding of viruses and other malware and how you can protect yourself.

Till next time, stay safe.