Damage to Objectives, Which are....what, exactly?

After finishing a game on howling Abyss just now, I checked the post-game stats as I usually do and found that all players' "Damage to Objectives" stat was the same as their "Damage to Turrets" stat. This got me thinking about what constitutes an objective in LoL. Obviously, this stat was incorrect as I remember taking the enemy inhibitor myself. Obviously, in this case the inhibitor did not count as an objective, but what about on Summoner's Rift, where Rift Herald, Baron Nashor, and Dragons dwell? I think each of these epic monsters is ubiquitous with map objectives, especially with casters almost always referring to said monsters as objectives. One could even go so far as to argue enemy jungle camps are objectives (albeit such a claim would be wholly situational).

Although this thread is intended to talk about what the game recognizes as an "Objective" I would like to add that it would be a nice addition to the game if a stat was added to summoner spells to display what they have done when they are moused over (ex: ignite dmg dealt, total # of successful cleanses, dmg blocked with barrier, etc.)

If you made it this far, thanks for reading my thoughts! Comment with any feedback you may have!

~GsO