We are still actively working on the spam issue.
DDOS stands for Distributed Denial Of Service.
A DDOS is a form of computer attack in which a victim is overwhelmed with network requests from multiple attackers (often from a botnet), causing the victim to be unable to serve appropriate responses to legitimate network traffic (e.g. a website being unable to send you it's homepage). DDOS's are considered a rather unsophisticated attack, rather their simplicity is what makes them effective.
Types of Denial of Service Attacks
Denial of Service covers a number of attack types. TCP SYN floods, ICMP floods, and DNS overloads are all examples of DDOS attacks.
Use of a Denial of Service Attack
A Denial of Service attack is primarily used to prevent use of a service, typically shutting down a webpage. This can be used in other ways, such as blinding network monitoring software to a real attack. Denial of Service attacks are also less commonly used to provide the necessary traffic load for failover attacks