DDoS attacks pose a serious threat to financial institutions. They function by overwhelming targets with excessive amounts of data traffic, denying customers access to services. To combat DDoS attacks, companies must implement strategies like putting hackers' IP addresses on a blacklist, monitoring networks for abnormal traffic patterns, and outsourcing security to specialist firms. While there is no perfect defense, applying best practices in computer security and hygiene can help thwart DDoS attacks and their impact on businesses.