Endosomes are a critical component of intracellular trafficking in eukaryotic cells. These organelles primarily function to sort, modify, and transport various molecules to their respective destinations within the cell. Some of the synonyms used to describe endosomes include "early endosomes", "late endosomes", and "recycling endosomes". Early endosomes are responsible for the initial sorting and trafficking of incoming molecules from the cell membrane and are characterized by their low pH and presence of early endosomal markers. Late endosomes are characterized by a more acidic pH and presence of late endosomal markers, indicating their role in the degradation and recycling of cellular components. Recycling endosomes, on the other hand, function to return certain molecules back to the plasma membrane, allowing for their reuse by the cell.