Social engineering is a method where hackers exploit human psychology to deceive individuals into giving up sensitive information, without the need for technical expertise. It can involve tactics like phishing, spear phishing, vishing, smishing, pretexting, baiting, and tailgating. Real-life examples, such as the Twitter hack in 2020 and the Target breach in 2013, demonstrate the dangers of social engineering. To defend against such attacks, individuals should be cautious of unsolicited messages, never give out passwords or OTPs, and verify URLs, while organizations should train staff, use email filters, implement access controls, and monitor for suspicious activity.