Threat cluster
Malware: Types, Delivery and Defence
Malware is the umbrella term for any software written to harm, hijack or exploit a device. Viruses are one small branch of it, and no longer the branch that matters most.
This hub explains each threat type in plain language, then points to the removal guide for it.
The malware families that actually reach home users
The threat landscape a US home user meets today is dominated by four things: infostealers that empty a browser's saved credentials, ransomware that encrypts files, adware bundled into free downloads, and phishing that needs no malware at all.
Classic self-replicating file viruses are now a small minority of incidents, even though 'virus' remains the word everyone uses.
- Infostealers — steal saved passwords, autofill data and session cookies
- Ransomware — encrypt files and demand payment for a decryption key
- Trojans — legitimate-looking programs that deliver a payload once run
- Adware and potentially unwanted programs — monetise browsing, arrive bundled
- Spyware and stalkerware — covert monitoring, sometimes installed by someone you know
- Rootkits — concealment layers that hide other components from the operating system
- Worms — spread across networks without user action
How malware actually gets in
Delivery has shifted almost entirely to the user's own actions. Cracked software and game cheats, fake installers promoted through search advertisements, malicious email attachments, and browser notification spam account for most consumer infections — not exotic exploits.
That is why web protection, careful downloading and patching matter as much as the detection engine you choose.
What protection can and cannot do
A good security product blocks known threats, flags suspicious behaviour and stops most malicious sites before they load. It cannot undo a credential that has already been stolen, decrypt files without a key, or override a decision to run something you were warned about.
Backups and two-factor authentication cover exactly the ground that antivirus cannot.
Threat explainers
Already infected? Start here
Products commonly used against these threats
Frequently asked questions
- What is the difference between malware and a virus?
- Malware is the whole category of malicious software. A virus is one type within it that attaches to files and self-replicates. Most modern threats are trojans and infostealers, not viruses.
- What is the most common malware today?
- Infostealers, which harvest saved browser passwords and session cookies, along with adware bundled into free downloads. Both usually arrive through a download the victim went looking for.
- Can malware infect a Mac or a phone?
- Yes. macOS faces adware and infostealers, and Android faces malicious apps and banking trojans. Volume is lower than on Windows, but neither platform is immune.
- Does antivirus stop all malware?
- No product stops everything. Detection plus safe download habits, prompt patching, offline backups and two-factor authentication is what actually reduces risk.