DDoS

A Denial of Service (DoS) attack is a type of an external intrusion used by malicious hackers to shut down the web servers of organizations – banking, commerce, government, and trade companies – by flooding or crashing them and exploiting vulnerabilities in their systems. Similarly, a Distributed Denial of Service (DDoS) attack is a more extreme, complex form of DoS because hackers infiltrate a system from more than one location, increasing the volume of machines flooding a system and making it more difficult to track and shut down.