1) Synchronous communication allows for real-time interaction between participants in online learning through tools like video conferencing, chat sessions, and phone calls. 2) It provides advantages like immediate feedback, motivation to prepare for scheduled sessions, and ability to do interactive activities like simulations and role playing. 3) Popular synchronous communication tools include Google Hangouts, Skype, chat boxes, and talkshoe, which enable activities like group video chats, screen sharing, file sharing, and discussions.