A Protein Database is a collection of information that stores data about proteins, which are essential molecules in living organisms. These databases contain details such as protein sequences, structures, functions, and interactions. Researchers use these resources to study proteins' roles in biological processes and diseases. One of the most well-known protein databases is the Protein Data Bank (PDB), which provides three-dimensional structures of proteins determined through techniques like X-ray crystallography and NMR spectroscopy. Other databases, such as UniProt, focus on protein sequences and functional information, aiding scientists in their research and discoveries.