Malware is not a single type of threat but a category. The major families include: viruses (attach to files and spread when shared), worms (spread automatically across networks), trojans (disguise themselves as legitimate software), ransomware (encrypt files and demand payment), spyware (silently collect information), and adware (display unwanted advertising).
Most malware infections follow a three-step lifecycle. Infection: the malware reaches the device through phishing, a malicious download, a compromised website, or a USB drive. Persistence: it installs itself to survive reboots. Payload: it carries out its actual purpose — encrypting files, stealing data, mining cryptocurrency, or sending spam.
Malware often operates silently for days, weeks, or months before its payload activates. Ransomware, for example, may quietly map every file on a network for weeks before encrypting everything simultaneously. This silence makes detection difficult and reaction-based defense insufficient.
The entry points for malware are consistent: email attachments, malicious links, drive-by downloads from compromised websites, pirated software, and physical media. Avoiding these entry points — not just relying on detection — is the foundation of malware defense.