According to the Vatican's announcement, the Pope will answer a faith-related question for his first tweet on December 12. Followers can send in questions using the hashtag #askpontifex or #B16.
Vatican communications adviser Greg Burke told reporters that the Latin handle @Pontifex was chosen because it means both "pope" and "bridge-builder."
"We are going to get a spiritual message. The Pope is not going to be walking around with a Blackberry or an iPad and no-one is going to be putting words into the Pope's mouth," Burke said.