Terminology

991 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 areas991 Architecture Fundamentals38 Distributed Systems73 Data Architecture71 Cloud Architecture55 Networking51 API & Integration Architecture45 Reliability & Resilience40 Observability33 Performance & Capacity Engineering34 Security Architecture50 Cost Architecture & FinOps30 Business Architecture28 Architecture Communication27 Enterprise Architecture27 Legacy Modernization27 AI-Era Architecture34 Software Architecture & Engineering37 Architecture Patterns34 Architecture Decision-Making30 The Architect's Meta-Skills27 Delivery & Release Engineering20 Platform Engineering & Developer Experience20 Testing & Quality Architecture20 Data Platform Architecture20 Streaming & Real-Time Data20 Data Governance & Semantics20 Frontend & Experience Architecture20 Edge, Mobile & IoT20 Regulatory & Data Protection Architecture20 Assurance, Audit & Model Risk20

Kind Any concept379 practice294 pattern166 metric55 tool36 protocol35 case-study26

10 terms shown.

Term	Kind	Topic	What it is
Changelog Stream	concept	Stream-Table Duality	A stream whose records are keyed updates, so replaying it from the beginning reconstructs a table — the same information in the other of its two forms.
Event Time Versus Processing Time	concept	Windowing	The distinction between when something happened and when the system saw it, which determines whether results are reproducible.
Freshness Requirement	concept	Streaming vs Batch	How stale data may be before the decision it supports degrades — the only question that justifies streaming over batch.
Key Skew	concept	Partition Keys & Ordering	An uneven distribution of records across partitions, which caps throughput at the busiest partition regardless of how many exist.
Poison Message	concept	Dead Letter Handling	A record that a consumer cannot process and cannot skip, which halts its partition entirely until someone intervenes.
Reprocessing Window	concept	Backfill & Reprocessing	How far back a pipeline can be replayed, set by the shortest retention anywhere along the path rather than by intent.
Schema Compatibility Mode	concept	Streaming Schema Evolution	The rule stating which schema changes a registry will accept, which encodes whether producers or consumers are expected to upgrade first.
Serving Latency Budget	concept	Real-Time Serving Layer	The end-to-end time from an event occurring to its effect being queryable, allocated across ingest, processing and serving.
Transaction Log Stream	concept	CDC to Stream	Change events derived from a database's write-ahead log — faithful to the table's mutations and to its internal model rather than to the business's.
Unbounded Dataset	concept	Streaming & Real-Time Data	Input with no known end, which removes the option of waiting for completeness and forces every aggregate to be provisional.