Essays are broken down into three (3) broad and general categories by function or purpose. Essays SHOULD Educate, Enlighten or Entertain. They are light, quick reads.
Sometimes the lines between the categories blur but don't worry. Classification or labeling such a scheme is somewhere between black magic and a crap shoot, a lost art.
Put another way, it just attaches a label of convenience & it is ALL RELATIVE.
It doesn't matter.
INFLUENCERS: Thomas Jefferson, Gilbert Chesterton, John L Stephens, Ambrose Bierce, Samuel Clemens, Will Rogers