This document discusses e-materials, which are digital learning materials published electronically. It defines e-materials as soft copies that are created and shared through electronic devices, requiring some technical knowledge but allowing for easy editing and updating. Some examples of e-materials for teaching include e-books, e-journals, websites, films, and graphics. E-books are like printed books but in digital format and can be read on computers or devices. E-journals are also available digitally and allow for up-to-date information. Overall, the document argues that e-materials can help improve student performance through immediate access to information while also reinforcing knowledge, though they may be distracting and require management.