Identity theft occurs when someone steals personal information like credit card or Social Security numbers and uses them fraudulently. Thieves can commit credit card fraud, open phone and utility accounts, take loans, or file fraudulent tax returns using a victim's identity. Victims can face financial costs and damaged credit. Key techniques used by thieves include dumpster diving, skimming, phishing, and social engineering. To protect yourself, shred documents with personal information, use strong passwords and updates, enable security software, monitor accounts, and file a police report if identity theft occurs.