# Observability
Observability is the ability to understand what a system is doing from its external signals.
## Start Here
- [[Field Notes/Incident Review]]
- [[Field Notes/Runbook]]
- [[Field Notes/SLO]]
- [[Field Notes/Tail Latency]]
## Projects
- [[Projects/Uptime Monitor]]
- [[Projects/SRE Terminal Debugger]]
## Related Topics
- [[Topics/Production Engineering]]
- [[Topics/Distributed Systems]]