E-learning refers to electronic learning systems that provide teaching through electronic resources and the internet. There are 10 types of e-learning including computer-managed learning, computer-assisted instruction, synchronous online learning, and asynchronous online learning. E-learning aims to increase student engagement with materials and independent learning skills. It can be implemented through websites, links, chats, quizzes and databases. While e-learning provides benefits like flexibility, cost savings and personalized learning, it also faces challenges such as lack of face-to-face interaction, technical issues, and security/authentication concerns.