Lipid droplets (LDs) are dynamic organelles found in nearly all cells, serving as hubs for lipid metabolism and other cellular functions. LDs are composed of a hydrophobic core of neutral lipids, separated from the aqueous cytosol by a monolayer of phospholipids. They are involved in lipid storage, membrane synthesis, viral replication, and protein degradation. LDs are linked to various physiological and pathological conditions, including obesity and metabolic diseases. Despite their widespread presence, many aspects of LD biology remain unknown. Recent advances in research have provided new insights into LD function and regulation. This review covers the current knowledge of LD cell biology, including their general properties, multiple functions, formation, growth, proteins associated with LDs, interactions with other organelles, movement within cells, and catabolism. LDs are also discussed in the context of physiology and disease, particularly in adipose tissue, liver, and small intestine.Lipid droplets (LDs) are dynamic organelles found in nearly all cells, serving as hubs for lipid metabolism and other cellular functions. LDs are composed of a hydrophobic core of neutral lipids, separated from the aqueous cytosol by a monolayer of phospholipids. They are involved in lipid storage, membrane synthesis, viral replication, and protein degradation. LDs are linked to various physiological and pathological conditions, including obesity and metabolic diseases. Despite their widespread presence, many aspects of LD biology remain unknown. Recent advances in research have provided new insights into LD function and regulation. This review covers the current knowledge of LD cell biology, including their general properties, multiple functions, formation, growth, proteins associated with LDs, interactions with other organelles, movement within cells, and catabolism. LDs are also discussed in the context of physiology and disease, particularly in adipose tissue, liver, and small intestine.