Twitter boss posts first video on social network

The video showed an edited sequence of food being
 prepared

Twitter boss Dick Costolo has posted the first video tweet, demonstrating how to make steak tartare in six seconds.

He posted the embedded video using an app from start-up Vine, which Twitter bought last year.

In keeping with the micro-blog's ethos, Vine is designed to enable users to post videos no longer than six seconds.

They will also be able to follow other Vine users and search for clips from people they know.

It is expected to be available initially as a standalone app from the Apple store.

"Video will be the next new front in the battle to add more functionality to social platforms," said Adrian Drury, lead analyst with research firm Ovum.