This document discusses cyber security and major cyber threats. It begins with an introduction to how the internet is used for email, research, downloading files, discussion groups, games, education, friendship, and reading electronic publications. It then outlines major security problems like viruses, hackers, phishing, trojans, and password cracking. Viruses replicate by modifying other programs and inserting code. Hackers exploit weaknesses to gain access. Trojans appear legitimate but take control. Password cracking recovers passwords. Phishing disguises communications to steal information. Cyber crimes are divided into those against people, property, and government. The document concludes by thanking the viewer and providing contact information.