In the past under other Government-run space projects, the first stage booster then just drops down into the ocean and is not recovered. Verrry expensive!
Instead, for the third successful time in a row, this private company has got the booster to carry on and alight on a barge, to be recovered and re-used, Much, much cheaper!
Type "SpaceX" in the little site Googler doohickey at right for previous entries with more info on the logistics of this achievement.
during the THAICOM 8 mission on May 27, 2016.
More info: http://www.spacex.com/news/2016/05/27...