# Reference

Reference material is **information-oriented**: precise, complete, and authoritative. Use this section when you need to look something up — not to learn a concept, but to verify a detail.

This section contains:

- **Core Concepts** — the ReSim data model: projects, systems, experiences, builds, batches, and metrics
- **Metrics Library** — the full API reference for the ReSim open-core metrics library (Python and C++)
- **Open Core Libraries** — API references for transforms, curves, math, time, visualization, and autonomy-log utilities