LXML is a Python library that allows for parsing XML and HTML documents. It is known for its speed and ease of use, providing a convenient API for navigating and modifying the document tree. LXML combines the power of the libxml2 and libxslt libraries with the simplicity of Python, making it an effective tool for web scraping and data extraction. It supports XPath, XSLT, and other advanced XML processing techniques, enabling the extraction of data from complex and nested documents. LXML is widely used in conjunction with other Python libraries like Beautiful Soup and Scrapy.