Jitter
In plain terms
Variation in the delay of received network packets.
Going deeper
Jitter is the inconsistency in packet arrival timing, which harms real-time applications like voice and video. Steady timing matters more than raw speed for these.
Under the hood
Buffers smooth jitter at the cost of latency; high jitter degrades calls and streaming.
Examples
VoIP quality, video calls, streaming, real-time gaming, QoS.
Think of it like...
Like a drummer with an unsteady beat, the unevenness, not the tempo, ruins the rhythm.