E-learning refers to a learning system that uses electronic resources and the internet to provide education to students. There are two main types of e-learning: synchronous and asynchronous. Synchronous e-learning involves real-time interaction between students and instructors who are in different locations. Asynchronous e-learning is self-paced and does not require real-time interaction, allowing students and instructors to engage with course material at different times. Examples of synchronous learning include virtual classrooms and video conferencing, while asynchronous learning uses resources like online courses, discussion forums, and message boards that can be accessed at any time.