PyPDF2 is a popular Python library used for working with PDF files. It allows users to perform various tasks such as reading, merging, splitting, and modifying PDF documents. With its simple interface, developers can easily extract text, images, and metadata from PDFs, making it a valuable tool for data processing and automation. The library is open-source and compatible with Python 3, which means it can be freely used and modified by anyone. PyPDF2 is particularly useful for applications that require handling large volumes of PDF files, such as document management systems and data analysis projects.