ElementTree is a built-in Python library used for parsing and creating XML (eXtensible Markup Language) documents. It provides a simple and efficient way to navigate, search, and modify XML data structures. With its easy-to-use API, developers can read XML files, extract information, and manipulate elements without needing extensive knowledge of XML syntax. The library represents an XML document as a tree structure, where each node corresponds to an element in the XML. This hierarchical representation allows for straightforward access to parent and child elements, making it easier to work with complex XML data. Overall, ElementTree is a valuable tool for anyone dealing with XML in Python.