Norbert Wiener's work during World War II laid the foundations for the field of computer ethics. His book discussed the purpose of human life, principles of justice, applied ethics methods, and key computer ethics topics and issues. One of the largest early computer crimes occurred from 1970-1973 when a bank teller embezzled over $1.5 million by hacking hundreds of customer accounts. In 2013, hackers briefly crashed stock prices by tweeting a false report that President Obama had been injured in an attack. Professional organizations have established ethics codes to guide computing professionals and users. Common computer crimes include financial fraud, hacking, software and hardware piracy, and computer viruses. Data security relies on physical safeguards, access controls,