# Background

- [Main concepts](/background/main-concepts.md)
- [Sequences](/background/sequences.md)
- [Label queue mechanics](/background/label-queue-mechanics.md): The label and review queue make it easy for teams to efficiently work on a dataset together.
- [Labeling metrics](/background/labeling-metrics.md)
- [3D Tiles](/background/3d-tiles.md)
- [Security](/background/security.md)