Real-Time Communications is a methodology that lets a device communicate in real time without transmission delays using peer-to-peer architecture. Examples of RTC include the Internet, land lines, mobile/cell phones, instant messaging (IM), Internet relay chat, video conferencing, teleconferencing and robotic telepresence. Emails, bulletin boards and blogs are not RTC channels but occur in time-shifting mode, where there is a significant delay between data transmission and reception.