E-learning uses computers and networks to provide educational content asynchronously or synchronously. Asynchronous learning allows for individual self-paced study, while synchronous options include video conferencing classes. E-learning systems consist of educational content, communication tools, and content management systems to organize materials. Content includes text, images, videos and interactive elements like quizzes. Communication tools facilitate discussion through wikis, bulletin boards, blogs and chats. Content management systems help manage these resources. While e-learning formats vary by browser, standards like MathML aim to represent mathematical expressions consistently across platforms.