Trace
In plain terms
The full record of a request's path through a system.
Going deeper
A trace assembles all the spans for one request into an end-to-end timeline across services. It shows the complete journey and where time went.
Under the hood
Identified by a trace ID; visualized as a waterfall of spans to spot slow segments.
Examples
Distributed tracing, request timelines, Jaeger, latency waterfalls, debugging.
Think of it like...
Like the complete itinerary of a package, every stop and how long each took.