Profile: Jack Dorsey

Factfile

Age:38

Occupation: chief executive of Twitter and Square

Appearance: over-caffeinated hipster tech-bro

Newsworthiness: has just returned to Twitter to try and save the company he founded

Jack Dorsey is busy. Very, very busy. He was ousted from the position of chief executive of Twitter all the way back in 2008. Last week, he formally returned to try and guide the flagging bird back to relevance.

Dorsey had already replaced Dick Costolo, who ...