**Micro-blogging service Twitter has been taken offline in what the company believes is a co-ordinated attack.**The popular site has been subject to a so-called denial-of-service attack, according to the company’s status blog.
Denial-of-service attacks take various forms but often involve a company’s servers being flooded with data in an effort to disable them.
It is not yet clear when the outage began or whether the service has suffered a global blackout.