The document outlines three themes for a history exam essay: diseases and epidemics, the 20th century including WWI and WWII, and food. For diseases, it mentions discussing the spread of illnesses like the Spanish flu and Black Plague. For food, it lists discussing gender roles in hunting versus home preparation, food indicating social status and types consumed, and how food related to globalization, trade, and shared cuisines. The final theme involves technology and how communication, medicine, and weapons evolved over time and helped expand empires and trade.