API
An application programming interface: a defined way for software components to exchange requests, events, or information. An API’s useful meaning includes its documented behavior, not only its endpoint names.
Read in context →GLOSSARY / BUILD YOUR VOCABULARY
LESS JARGON.
MORE PRECISION.
Working definitions for the field guides. Follow each reading link for context, examples, and the relevant primary reference.
HFT
High frequency trading. In this site’s educational context, the emphasis is on timing-sensitive automated workflows and their engineering controls, not a universal numerical threshold or a promised level of performance.
Read in context →Market-data snapshot
A representation of market state at a defined context. An integration must understand how later updates relate to that snapshot and how it recovers a consistent view.
Read in context →Order book
A representation of buying and selling interest exposed by a venue or data service. What is visible depends on the feed’s scope and semantics.
Read in context →Acknowledgment
Evidence that a request reached a particular stage in a provider’s workflow. Its exact meaning is service-specific and should not automatically be equated with execution.
Read in context →Reconciliation
Comparing and resolving local order or account state against supported authoritative evidence after ordinary processing or an interruption.
Read in context →Latency
Elapsed time between named events. Meaningful comparisons specify the boundaries, workload, clock assumptions, and distribution being measured.
Read in context →FIX
A trading-message standard maintained by the FIX Trading Community. Read the protocol guide and its primary reference to distinguish message meaning, session behavior, and representation.
Read in context →REST
An architectural style used for web interfaces, often encountered through HTTP request-response APIs. The label alone does not establish order semantics or recovery behavior.
Read in context →WebSocket
A protocol supporting persistent, bidirectional communication. A stream still needs application-level handling for state, freshness, interruptions, and recovery.
Read in context →Binary encoding
A representation of data using a defined binary layout. Performance must be measured with equivalent semantics and validation rather than assumed from the format label.
Read in context →RPC
Remote procedure call: a mechanism for requesting an operation from another system. An RPC response establishes only what the method’s documented contract says it establishes.
Read in context →Exposure reservation
An internal allocation of risk capacity for an authorized action that may still create an obligation, including an order awaiting a known outcome.
Read in context →Tick value
The monetary effect of a minimum price increment for a contract under its actual quotation and payoff convention. The futures guide uses a fictional linear example to demonstrate unit conversion.
Read in context →Margin
An account or collateral requirement whose meaning and calculation depend on the product and provider. It should not be confused with notional exposure or a guarantee about maximum loss.
Read in context →Kill switch
An operational control whose actual effects must be defined: for example, blocking new activity, requesting cancellation, and reconciling remaining obligations. Its label is not proof that every external order has vanished.
Read in context →Confirmation policy
A stated requirement for the evidence used before an application relies on an observed onchain outcome. Distinguish that policy from merely receiving a submission response.
Read in context →