This guide introduces key terms related to distributed systems and Temporal, a service and library that ensures code never gets stuck in failure at the application or platform level. Core concepts include concurrency, scalability, reliability, eventual consistency, strong consistency, CAP theorem, ACID properties, atomicity, isolation, durability, durable execution, idempotent function, deterministic function, platform, application, event sourcing, Temporal, Worker, Workflow, Activity, Query, Signal, retry, Cluster, and History. Understanding these terms can help you engage in conversations about distributed systems and Temporal with confidence.