> ## Documentation Index > Fetch the complete documentation index at: https://docs.gbox.ai/llms.txt > Use this file to discover all available pages before exploring further. # Concepts > This conceptual guide introduces the two core abstractions in GBOX: **Devices** and **Boxes** ## Device A **Device** is the underlying hardware resource (cloud virtual/physical Android devices, registered local Android device, Linux desktop/sandbox). * Devices are the foundation for creating boxes. * A device can only host **one active box at a time**. ## Box A **Box** is an operable environment created from a device. * Think of it as a running session on that device. * Each device can create multiple boxes **over time**, but you must terminate the current one before starting another. * Boxes expose the APIs and SDK actions your AI agents use to interact with the device environment. Concepts