A breach is any incident that results in unauthorized access to computer data, applications, networks, or devices. The list of breaches is long. A few notable examples include:
Yahoo: 3 billion user accounts were compromised in 2013 after a phishing attempt gave hackers access to the network.
Facebook: Internal software flaws led to the loss of 29 million users’ personal data in 2018, including Facebook founder and CEO Mark Zuckerberg’s personal information. Early 2021, 533 million users’ data was leaked online.