On the other side of the ledger is Chicago at +6, this means the Bulls are “getting” 6 points (or are 6-point underdogs). A wager on Chicago would score for you if the Bulls either prevail outright, or lose by less than 6 points (e.g. Bulls 101, Lakers 105 would give you a winning bet if you took the Bulls +6).
The point spread is the expected final score difference between two teams. It is represented as both a negative and positive number; if the spread is 3 points, you'll see that as both -3 and +3. The team that is the favorite to win gets the minus-number (-3); the underdog gets the plus-number (+3).
For example: Green Bay –6.5 means that Green Bay is the favorite and must win by at least 7 points. Chicago +6.5 means that Chicago is the underdog and has been “spotted” or “given” 6.5 points; if Chicago loses by 6 or fewer points, it is a winning bet (if Chicago pulls an outright upset, it is also a winning bet).