Herons, egrets, and bitterns are birds in the family Ardeidae, they are most closely related to the families Ciconiidae (Storks) and Threskiornthidae (Ibises and Spoonbills), these are the only three extant families of the order Ciconiiformes, ardeids are sometimes mistaken for cranes, but they are very different from them and not closely related to them, cranes (family Gruidae) belong to a whole different order, which is the order Gruiformes, which also includes the limpkin, trumpeters, sarothurids, finfoots, and members of the rail family, gruiform waterbirds are more closely related to shorebirds (order Charadriiformes) while ciconiiform waterbirds are more closely related to the pelicans, cormorants, shags, darters, frigatebirds, boobies, gannets, tropicbirds, shoebill, hamerkop, sunbittern, and kagu of the order Pelecaniformes, the orders Gruiformes and Charadriiformes are grouped together within the clade Gruicharadriae whilst the orders Ciconiiformes and Pelecaniformes are classified together within the clade Ciconiopelecanae.
Many species of herons & egrets (from the genus Ardea & Egretta) do look similar though to an untrained eye. Even though egrets are generally white and herons are generally multicolored, this is rather inconsistent since a few heron species actually have white morphs like mentioned in the video where they basically look like typical egrets. Also, a few egret species like the Reddish Egret and Slaty Egret aren't actually white and resemble typical herons in some way. Not to mention that even though Herons are generally placed under the genus Ardea & Egrets in Egretta, there are a few exceptions; e.g. Black Heron, Tricolored Heron, Little Blue Heron are placed in Egretta while the Great Egret & Intermediate Egret are in Ardea.
