What are the different types of malware and how do they work?

Malware (malicious software) is designed to damage, disrupt, or gain unauthorized access to computer systems.\n\n**Major malware types:**\n\n**1. Viruses:**\n• **How they work** - Attach to legitimate files and replicate when executed\n• **Spread method** - Through infected files, email attachments, removable media\n• **Example** - ILOVEYOU virus (2000) infected 50M+ computers via email\n\n**2. Worms:**\n• **How they work** - Self-replicating programs that spread across networks\n• **Spread method** - Exploit network vulnerabilities without user interaction\n• **Example** - WannaCry ransomware worm (2017) affected 300k+ computers\n\n**3. Trojans:**\n• **How they work** - Disguise as legitimate software to trick users\n• **Purpose** - Create backdoors, steal data, or download additional malware\n• **Example** - Banking trojans that steal financial credentials\n\n**4. Ransomware:**\n• **How they work** - Encrypt files and demand payment for decryption key\n• **Impact** - Can paralyze entire organizations and critical infrastructure\n• **Example** - Colonial Pipeline attack (2021) disrupted US fuel supply\n\n**5. Spyware:**\n• **How they work** - Secretly monitor and collect user information\n• **Data stolen** - Passwords, browsing habits, personal information\n• **Example** - Keyloggers that record keystrokes\n\n**6. Adware:**\n• **How they work** - Display unwanted advertisements and track behavior\n• **Impact** - Slows system performance and compromises privacy\n\n**Protection strategies:**\n• Use reputable antivirus software\n• Keep systems and software updated\n• Avoid suspicious downloads and email attachments\n• Regular system backups\n• Network segmentation and access controls