In computer networking, latency, or delay is an articulation of how much time it takes for a data packet to travel from one defined point to another. One can measure the network latency by determining the round-trip time (RTT) for a data packet to travel to a destination and back again.
During live streaming, the latency occurs when the camera captures an event, and the specific event being displayed to viewers. Latency also depends on which type of channel you have. It might be longer if your device is using too many resources to push through the encoder signal or your upload connection is slow. It can occur at any phase of the live streaming including, Image Capture, Encoding, Transmission, Jitter Buffer, Transcoding & Transrating, Transmission to Viewers, Decoding & Display.
Remember that, lower latency is not as important if you do not interact with your audience.