Jargon Buster

Build

APIs & Integrations

How systems talk to each other.

The territory

30 core terms mapped for this field, ranked by how often builders reach for them. Each one is a future entry. Want to bust one? One entry, one file, one pull request.

  • WebhookURL you expose that another service POSTs events to"have it ping my app when something happens" · "reverse API call"
  • REST APIResource-based HTTP interface using verbs and URL paths"normal API with URLs" · "the regular kind of API"
  • API KeyStatic secret string identifying the caller on each request"the secret code you paste in" · "the token thing from the dashboard"
  • Rate LimitCap on requests per window before the API rejects you"it cuts me off if I call too fast" · "429 errors"
  • EndpointOne callable URL + method on an API"the specific address you hit" · "the route you call"
  • HTTP Status Codes (2xx/4xx/5xx)Numeric result classes signaling success, client error, server error"what does a 404 mean" · "the number it sends back"
  • PayloadThe body of data sent or returned in a request"the actual stuff being sent" · "the JSON blob"
  • Query Parameters vs Path Parameters vs Request BodyThree places to put input on a request"the bit after the question mark" · "where do I put the inputs"
  • Content-Type / MIME TypeHeader declaring the format of the body"the application/json header" · "it says wrong format"
  • PollingRepeatedly asking an API whether anything changed"check every few seconds" · "keep asking if it's done yet"
  • TimeoutMax wait before abandoning an outbound call"it just hangs forever" · "give up after 30 seconds"
  • Idempotency KeyClient-supplied ID so retries don't duplicate an operation"so it doesn't charge them twice" · "safe to retry"
  • Exponential BackoffRetry with progressively longer waits after failures"wait longer each time it fails" · "don't hammer it"
  • CORSBrowser rule controlling which origins may call an API"blocked by the browser" · "works in Postman but not my site"
  • Pagination (Cursor vs Offset)Fetching results in chunks via page tokens or offsets"only gives me 100 at a time" · "how do I get the next batch"
  • API ProxyYour server relays calls to hide keys and reshape data"call it from my server instead" · "hide the key behind my backend"
  • GraphQLQuery language where the client specifies exact fields returned"ask for only the fields I want" · "one endpoint for everything"
  • Webhook Signature VerificationChecking an HMAC header proves the webhook is genuine"make sure it's really from them" · "signing secret"
  • OpenAPI SpecificationMachine-readable contract describing an API's endpoints and shapes"the swagger file" · "the openapi spec"
  • SDK / Client LibraryLanguage-native wrapper hiding raw HTTP calls"the official package" · "the npm thing instead of curl"
  • Sandbox / Test ModeFake-data environment for integrating without real effects"practice mode" · "test keys"
  • Message QueueBuffer that holds jobs for workers to consume later"put it in line to process later" · "the backlog pipe"
  • Integration Platform as a Service (iPaaS)Hosted service wiring apps together via triggers and actions"the Zapier kind of thing" · "connect app A to app B"
  • Server-Sent Events (SSE)One-way streaming push from server to browser over HTTP"stream text as it arrives" · "like ChatGPT typing"
  • WebSocketPersistent two-way connection for live bidirectional messages"keep the line open" · "real-time back-and-forth"
  • Asynchronous Job PatternReturn immediately with a job ID, notify when done"it takes too long to wait" · "kick it off and tell me later"
  • Data Mapping / Field MappingTranslating one system's field names into another's"match their columns to mine" · "the translation table"
  • CRUDCreate, read, update, delete: the four basic operations"the basic four things" · "add edit delete list"
  • API VersioningFreezing an API shape so upgrades don't break clients"don't break my old code" · "the v1 in the URL"
  • Batch / Bulk EndpointOne call that operates on many records at once"send 500 at once" · "avoid a call per row"

Deeper in the field

  • HTTP Methods Request verbs such as GET, POST, PUT, PATCH, and DELETE
  • Request Headers Metadata controlling format, authentication, caching, and request behavior
  • Error Response Structured failure body with a stable code, message, and details
  • API Documentation Human-readable instructions, examples, limits, and authentication requirements
  • multipart/form-data Encoding for uploading files alongside fields
  • Presigned URL Temporary link authorizing a direct upload or download
  • Serialization / Deserialization Converting application data to and from formats such as JSON
  • Long Polling Holding a request open until data arrives or timeout
  • Fan-out One event dispatched to many downstream consumers
  • Event Bus / Pub-Sub Publishers emit events, subscribers react independently
  • At-Least-Once Delivery Guarantee that messages arrive, possibly duplicated
  • Deduplication Detecting repeated requests or events so effects happen only once
  • Retry Policy Rules for which failures retry, how often, and how long
  • Circuit Breaker Stop calling a failing dependency until it recovers
  • Dead Letter Queue Holding pen for messages that repeatedly failed processing
  • Middleware Code that intercepts requests before your handler runs
  • API Gateway Front door that routes, authenticates, and throttles API traffic
  • Backend for Frontend (BFF) Backend built for one client, serving exactly what it needs
  • Response Normalization Reshaping third-party output into your own schema
  • ETag / Conditional Request Cache validator letting servers reply "not modified"
  • gRPC Fast binary RPC protocol using protobuf contracts
  • RPC-style API Endpoints named as actions rather than resources
  • Webhook Replay Re-sending past events to recover from downtime
  • Sync Cursor / Watermark Saved position marking where the last sync stopped
  • Incremental Sync Transfer only records changed since the previous successful synchronization
  • Upsert Create a record when absent; otherwise update the existing record
  • Conflict Resolution Rules deciding which system wins when synchronized records diverge
  • Reconciliation Periodic full compare to fix drift between two systems
  • Eventual Consistency Connected systems may reflect the same update at different times
  • Schema Registry Central store of agreed data schemas producers and consumers validate against
  • API Deprecation Retiring an endpoint while giving clients time and guidance to migrate