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

27 terms shown.

Term	Kind	Topic	What it is
Capacity Insurance Reliability Headroom, Standby Capacity	concept	Waste Elimination	Capacity that produces no value in normal operation and exists to make failures survivable - which looks identical to waste on a utilisation dashboard and must be defended explicitly.
Cloud Egress Cost	concept	Network & Egress Costs	The asymmetric pricing where data entering a cloud is free and data leaving is charged, which shapes architecture more than most teams expect.
Cloud Pricing	concept	Cloud Pricing Models	How cloud providers charge, which dimensions dominate, and the pricing structures that reward architectural rather than operational responses.
Cloud Pricing Models	concept	Cost & FinOps	The purchase options for cloud compute — on-demand, committed use, and spot — which differ by up to 90% for identical hardware.
Commitment Floor Minimum Spend Obligation, Contracted Spend Floor	concept	Reserved & Committed Capacity	The minimum spend a contract obliges you to pay regardless of usage, which makes efficiency gains unrealisable until the term ends and therefore sets the pace of cost programmes and migrations.
Cost Driver Scaling Driver, Cost Dimension	concept	Architecture Cost Modelling	The measurable quantity whose growth causes a cost to grow - identifying it correctly is what makes a cost model predictive rather than descriptive.
Cost Telemetry Lag Billing Data Delay, Spend Reporting Latency	concept	Cost Governance	The delay between spend being incurred and appearing in billing data, which sets a floor on how fast any detective cost control can possibly react and explains why budget alerts arrive after the money is gone.
Cost versus Reliability	concept	Cost vs Reliability	Reliability is bought with redundancy and headroom, both of which cost money — so the target must be chosen rather than assumed.
Cost vs Reliability Trade-off	concept	Cost & FinOps	The non-linear relationship between availability and spend, which makes each additional nine roughly an order of magnitude more expensive.
Data Gravity Data Inertia, Locality Pull, Egress Pull	concept	Network & Egress Costs	The tendency of large data to attract compute and services toward it, because moving data across billed or slow boundaries is expensive while moving computation to the data is cheap.
Dual-Run Cost Overlap Migration Cost Hump, Parallel-Running Overlap	concept	Architecture Cost Modelling	The period in any platform migration when both the old and the new system are paid for at once, which raises the run rate before it falls and sets the true date on which a cost business case begins to pay back.
Egress Cost Data Transfer Out	concept	Cost & FinOps	The charge for moving data out of a cloud provider or across its zones and regions — usually the least-anticipated line on a cloud bill.
Egress Pricing	concept	Cloud Pricing Models	The asymmetric charging model in which data entering a cloud is free and data leaving is billed, shaping architecture more than compute pricing does.
Elastic Cost Blindness Soft Constraint Failure, Invoice-Delayed Feedback	concept	Cost Governance	The failure mode of elastic platforms - the system satisfies any request rather than refusing it, so a capacity problem becomes a cost problem that reports itself a month late.
Fully-Loaded Tenant Cost True Cost to Serve, Cost Per Tenant, Loaded Unit Cost	concept	Unit Economics	The total cost of serving one tenant including the per-tenant floors that do not scale with usage - infrastructure minimums, control-plane overhead, fleet operations, support and abuse - which is what makes sm…
Hidden Cost Categories	concept	Total Cost of Ownership	The recurring costs routinely omitted from total-cost-of-ownership comparisons, which usually exceed the licence or infrastructure line everyone argues about.
Idle Cost	concept	Cost per Request	The portion of infrastructure spend incurred regardless of traffic, which determines how cost per request behaves as volume changes.
Interruption Tolerance	concept	Spot & Interruptible Capacity	The property that determines whether a workload can use heavily discounted pre-emptible capacity, defined by what happens when an instance is reclaimed at short notice.
Licence Costs	concept	Licence & Vendor Costs	Software licensing whose pricing model frequently constrains architecture more than its technical characteristics do.
Licence Metric Risk	concept	Licence & Vendor Costs	The exposure created when a software licence is priced on a unit that cloud architecture changes unpredictably, such as cores, sockets or instances.
Observability Cost	concept	Observability Cost	Monitoring spend that grows with traffic and frequently reaches a meaningful fraction of infrastructure cost — controlled by sampling, cardinality and retention.
Orphaned Resource	concept	Waste Elimination	Infrastructure that is billed but serves nothing, typically left behind when the thing it supported was deleted.
Pass-Through Cost of Goods Sold Third-Party Unit Cost, Supplier Pass-Through Term	concept	Cost per Request	The part of the cost of serving one unit that is paid to a third party per transaction, which infrastructure optimisation cannot reduce and which eventually decides whether unit cost keeps falling.
Retrieval-Cost Trap Archival Access Cost, Cold Tier Scan Penalty	concept	Storage Costs	The failure where moving data to an archival tier saves storage cost and a scanning access pattern then spends more on retrieval than the tiering saved.
Shared-Service Commons Free-at-Point-of-Use Platform, Uncharged Internal Platform	concept	Showback & Chargeback	The failure mode where cost allocation prices each team's own resources but leaves internal platforms free to use, so teams move cost onto the shared estate instead of removing it and total spend rises while e…
Storage Costs	concept	Storage Costs	Storage is cheap per gigabyte and expensive in aggregate — controlled by retention and tiering rather than by unit price.
Total Cost of Ownership TCO	concept	Total Cost of Ownership	The full lifetime cost of a choice — infrastructure, licences, and the engineering time that is usually the largest term and the one omitted.