Terminology

2185 terms, tools, patterns and metrics an architect is expected to use precisely. Each one gets a short explanation of what it is, and — where it matters — what it is commonly confused with. Search filters as you type; the column headers sort.

All areas2185 Architecture Fundamentals77 Distributed Systems107 Data Architecture110 Cloud Architecture89 Networking88 API & Integration Architecture82 Reliability & Resilience75 Observability70 Performance & Capacity Engineering72 Security Architecture81 Cost Architecture & FinOps66 Business Architecture67 Architecture Communication67 Enterprise Architecture66 Legacy Modernization66 AI-Era Architecture69 Software Architecture & Engineering71 Architecture Patterns71 Architecture Decision-Making63 The Architect's Meta-Skills61 Delivery & Release Engineering66 Platform Engineering & Developer Experience70 Testing & Quality Architecture66 Data Platform Architecture64 Streaming & Real-Time Data69 Data Governance & Semantics69 Frontend & Experience Architecture66 Edge, Mobile & IoT68 Regulatory & Data Protection Architecture65 Assurance, Audit & Model Risk64

Kind Any concept785 practice729 pattern362 metric125 case-study77 tool62 protocol45

18 terms shown.

Term	Kind	Topic	What it is
Alert Fatigue	concept	Observability	The desensitisation that follows from alerts that are frequent, non-actionable, or not tied to user impact — after which real alerts are missed too.
Alert Fatigue in Practice	concept	Alert Fatigue	The state in which alerts are ignored because most of them do not matter — a reliability failure caused by monitoring rather than prevented by it.
Alert on Symptoms Symptom-Based Alerting	concept	Alerting	Paging on user-visible impact rather than on internal conditions that may or may not cause it.
Cardinality	concept	Observability	The number of distinct time series produced by a metric, which is the product of the distinct values of all its labels — and the main driver of monitoring cost.
Counter Reset Handling Monotonic Counter Semantics, Rate Reset Compensation	concept	Metrics	The rule that a decrease in a cumulative counter is interpreted as a process restart rather than as negative work, which is what allows rates to survive deploys and what makes gauges-as-counters silently wrong.
Counter, Gauge and Histogram	concept	Metrics	The three fundamental metric types, distinguished by what they represent over time and by which aggregations are valid.
Distributed Trace	concept	Distributed Tracing	A causally-linked record of one request's path across services, composed of spans that carry timing, attributes and parent relationships.
Exemplar	concept	OpenTelemetry	A trace identifier attached to a metric data point, linking an aggregate measurement directly to a concrete request that produced it.
Liveness vs Readiness	concept	Health Checks	Two distinct questions - should this process be restarted, and should it receive new work - which must be answered by different checks with opposite sensitivities.
Log Schema Drift Field Type Drift, Telemetry Schema Breakage	concept	Structured Logging	The silent breakage of dashboards and alerts when a service changes the name, type or nesting of a structured log field, producing empty results rather than errors.
Metric Cardinality	concept	Cardinality	The number of unique label combinations on a metric, which determines the number of time series stored and is the main driver of monitoring cost and failure.
Metric Staleness Staleness Marker, Stale Series	concept	Metrics	The rules deciding how long a time series keeps answering queries after it stops being written - which determines whether a dead process's last value is served as current, and whether an alert on a vanished se…
Metric Temporality Delta Temporality, Cumulative Temporality	concept	OpenTelemetry	Whether a reported metric point carries a running total since a start time or only the change during one interval - the choice that decides whether process restarts or duplicate deliveries are what corrupts yo…
Metrics	concept	Metrics	Cheap pre-aggregated numeric time series — excellent for knowing something is wrong, structurally unable to tell you which request.
Observability	concept	Observability	The property of being able to answer new questions about a system's internal state from its external outputs, without shipping new code.
Span Link Trace Link, Span Reference	concept	Distributed Tracing	A pointer from one span to another span in a different trace, recording a causal relationship where no single enclosing parent exists - the mechanism that keeps batch jobs, fan-in consumers and delayed asynchr…
Symptom-Based Alerting Alert on Effects, User-Visible Alerting	concept	Alert Fatigue	Paging on what the user experiences and investigating causes with dashboards - because cause-based alerts fire in clusters during a single incident and bury the signal they exist to provide.
Wide Event Canonical Log Line, Arbitrarily-Wide Structured Event, Unit-of-Work Event	concept	Observability	A single structured record per unit of work carrying every field that might matter, aggregated only at query time - so questions nobody anticipated remain answerable, which pre-aggregated metrics make permanen…