In plain English
A sandbox lets you try things safely. Whatever happens inside stays inside, so a bug, a bad file or an AI agent making a mistake can't break anything that matters. Teams use sandboxes to test new features, open suspicious attachments and let AI tools write and run code.
Example
Before letting an AI agent run code on a company laptop, a team gives it a sandbox. The agent can install packages and run scripts there, but it can't read files or reach systems outside it.
Not the everyday meaning
A box of sand for children to play in.
Why it matters
Sandboxes are how teams say yes to risky things. Developers test changes without breaking the live app, security teams open suspicious files without infecting the network, and AI agents can write and run code without access to everything else. Many APIs also offer a "sandbox" version with fake data, so you can build against them before going live.
Common confusion
Sandbox vs. container. A sandbox is the goal: keep something isolated. Containers and virtual machines are common ways to build one. Not every container is locked down enough to count as a sandbox.