Protein-protein interactions refer to the ways in which two or more proteins bind together to perform specific biological functions. These interactions are crucial for various cellular processes, including signal transduction, immune responses, and the formation of cellular structures. Proteins can interact in different ways, such as through complementary shapes or chemical properties, allowing them to work together effectively. Understanding protein-protein interactions is essential for fields like biochemistry and molecular biology, as they play a significant role in maintaining cellular health and function. Disruptions in these interactions can lead to diseases, making them important targets for drug development and therapeutic interventions.