How can one team "own" another team's first-round pick?

Question

For instance, the byline to this Bleacher Report article reads "The Cleveland Cavaliers own the Brooklyn Nets' first-round pick in the 2018 NBA draft."

How can one team own another team's first-round pick?

Answer 1

Draft picks are an asset, and (in the NBA anyway) they can be traded between teams (subject to some restrictions). Whichever team has the pick on the day of the draft gets to select a player and have exclusive rights to that player, independent of which team the pick was originally assigned to - but the original assignment still determines where the pick falls in the order; hence the pick of a losing team like Brooklyn is more valuable than that of a winning team like the Warriors.

In this case, Brooklyn traded the pick to the Celtics as part of the Kevin Garnett/Paul Pierce trade, and the Celtics then further traded that pick to the Cavaliers as part of the Kyrie Irving/Isaiah Thomas trade.