logString

Logstring is a term used in computing to describe the text that constitutes a single log entry in a logging system. A logstring is typically the line or payload appended to a log file or transmitted over a log stream, and serves as a record of an event, state change, or diagnostic message. In many environments, a logstring encodes key information such as a timestamp, severity level, source component, and a human-readable description of the event.

Formats vary by system. Plain text lines are common for simplicity, while structured formats such as key=value pairs or JSON objects enable easier machine parsing, indexing, and correlation. Structured logging often includes fields like timestamp, level, service, instance, and message, and may add tracing identifiers for cross-service correlation.

Logstrings play a central role in operational practices. They support troubleshooting, auditing, and security monitoring, and feed into log aggregation, search tools, alerting systems, and SIEM platforms. In distributed architectures, linking related logstrings with trace or correlation IDs helps reconstruct end-to-end flows across services.

Examples: A plain-text logstring might look like "2025-12-11T12:34:56.789Z INFO [auth] User 'alice' logged in". A structured form could be {"ts":"2025-12-11T12:34:56.789Z","level":"INFO","service":"auth","message":"User 'alice' logged in","trace_id":"abcd1234"}.

See also: logging, log file, structured logging, log management, traceability.