Dr. Kamy Sepehrnoori is a professor in the Hildebrand Department of Petroleum and Geosystems Engineering at The University of Texas at Austin, where he holds the Texaco Centennial Chair in Petroleum Engineering. His research interest and teaching include computational methods, reservoir simulation, simulation of unconventional reservoirs, enhanced oil recovery modeling, flow assurance modeling, naturally fractured reservoirs, high-performance computing, and CO2 sequestration. He has been teaching at The University of Texas for over 35 years and has graduated more than 230 MS and PhD students under his supervision working mainly in the areas of reservoir simulation and enhanced oil recovery modeling. For the last several years, he has been supervising a research group in simulation of unconventional reservoirs (shale gas and tight oil reservoirs). Sepehrnoori’s research team along with his colleagues have been in charge of development of several compositional reservoir simulators (i.e., UTCOMPRS, UTCHEMRS, and UTGEL). Also, more recently, he supervised the development of a software package for embedded discrete fracture modeling for application in naturally and hydraulically fractured reservoirs. He has published more than 650 articles in journals and conference proceedings in his research areas. He has also coauthored three books, which have been published by Elsevier. Sepehrnoori is the director of the Reservoir Simulation Joint Industry Project in the Center for Subsurface Energy and the Environment. He holds a PhD degree in petroleum engineering from The University of Texas at Austin. Dr. Yifei Xu is a senior research engineer at ExxonMobil Upstream Research Company. His research interest includes reservoir simulation, reservoir modeling, gridding, naturally and hydraulically fractured reservoirs, and unconventional resources. He has published more than 15 technical papers in his research area. His contributions to this book come from his research as a PhD candidate at The University of Texas at Austin. He worked on the embedded discrete fracture model (EDFM) for more than 5 years, and he was one of the developers of an EDFM preprocessing code. He holds a PhD degree in petroleum engineering from The University of Texas at Austin. Dr. Wei Yu is the chief technology officer for Sim Tech LLC and a research associate in the Hildebrand Department of Petroleum and Geosystems Engineering at The University of Texas at Austin. He is an Associate Editor for the SPE Journal and the Journal of Petroleum Science and Engineering. His research interests include EDFM (Embedded Discrete Fracture Model) technology for modeling any complex fractures, shale gas and tight oil reservoir simulation, EDFM-AI for automatic history matching and complex fracture characterization. Yu has authored or coauthored more than 200 technical papers and two books (Shale Gas and Tight Oil Reservoir Simulation and Embedded Discrete Fracture Modeling and Application in Reservoir Simulation), and holds five patents. He holds a PhD degree in petroleum engineering from The University of Texas at Austin.