Search engine systems like Google and Yahoo! are essential tools for finding the most valuable and relevant information, given the explosion of digital information available today.  This course studies the design, implementation, and evaluation of modern information retrieval systems, such as web search engines.  Topics include: retrieval system design and implementation, text analysis techniques, retrieval models (e.g. Boolean, vector space, probabilistic, and learning-based methods), search evaluation, retrieval feedback, search log mining, and applications in web information management.