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System Design Glossary

First PublishedByAtif Alam

Short definitions for terms used in system design pages. For operational depth, follow the links in each topic page.

AbbreviationFull Form
APIApplication Programming Interface
CAPConsistency, Availability, Partition tolerance
CDNContent Delivery Network
DAUDaily Active Users
DBDatabase
FKForeign Key
GraphQLGraph Query Language
gRPCgRPC Remote Procedure Call
IDIdentifier
JSONJavaScript Object Notation
LRULeast Recently Used
NoSQLNot Only SQL
p9999th percentile (latency)
PACELCIf Partitioned: choose Availability or Consistency; Else: choose Latency or Consistency
QPSQueries Per Second
REDRate, Errors, Duration
RedisRemote Dictionary Server
RESTRepresentational State Transfer
SLAService Level Agreement
SQLStructured Query Language
TTLTime To Live
USEUtilization, Saturation, Errors
2PCTwo-Phase Commit