DDOS=Distributed Denial of Service
The bad guys single or group get together, hijack other computers and/or bots then in unison all at the same time over and over send requests to a certain address/site. The target address/site's server(s) get overwhelmed and it shuts down because it cannot handle all the requests. This is the easiest way to shut someone down. No brains involved just sheer brute force in numbers. Responsive site admins will identify and cut off the offenders, then bring the site back up.
let the blood rain!
brandon