This Alyson Michalka photo contains
snap brim hat, sombrero, boater, leghorn, panama, panama hat, sailor, skimmer, and straw hat.
There might also be
dress hat, high hat, opera hat, silk hat, stovepipe, top hat, topper, beaver, pith hat, pith helmet, sun helmet, topee, topi, cavalier hat, and slouch hat.