Google Cloud Functions lets you run your code without provisioning or managing servers. This deployment model is sometimes referred to as "serverless" or "Function as a Service" (FaaS).
A Google Cloud Function runs in an application on a container managed by Google. This lets you focus on writing code without worrying about the underlying application or infrastructure.
Google Cloud Functions are ephemeral. This means that the underlying container can be suspended or recycled when there's no request pending.