---
title: "Concepts"
description: ""
position: 2
---

NeMo Gym concepts explain the mental model behind building RL training environments: when to use RL over SFT, how environment components work together, and how verification signals drive learning. Use this page as a compass to decide which explanation to read next.

<Tip>
New to RL for LLMs? Start with [training-approaches](/v0.2/about/concepts/training-approaches) for context on SFT, RL, and RLVR, or refer to [Key Terminology](/v0.2/about/concepts/key-terminology) for a quick glossary.

</Tip>

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## Concept Highlights

Each explainer below covers one foundational idea and links to deeper material.

<Cards>

<Card title="Training Approaches" href="/v0.2/about/concepts/training-approaches">
Understand the differences between SFT, DPO, and GRPO, and the rise of RLVR.
</Card>

<Card title="Environment Components" href="/v0.2/about/concepts/core-components">
Understand the three server components that make up a training environment.
</Card>

<Card title="Configuration System" href="/v0.2/about/concepts/configuration">
Understand how servers are configured and connected.
</Card>

<Card title="Architecture" href="/v0.2/about/concepts/architecture">
How components interact during startup and rollout collection.
</Card>

<Card title="Task Verification" href="/v0.2/about/concepts/task-verification">
Understand the importance of verification and common implementation patterns.
</Card>

<Card title="Key Terminology" href="/v0.2/about/concepts/key-terminology">
Essential vocabulary for agent training, RL workflows, and NeMo Gym.
</Card>

</Cards>

---
