TAE distinguishes test environments by purpose and risk. User Acceptance Testing is typically performed in an environment that is as production-like as feasible (configuration, data shape, integrations) but still controlled and safe for testing activities. This is commonly referred to as preproduction (often "staging"): it supports realistic end-to-end flows, allows business users to validate that the SUT meets acceptance criteria, and enables running routine/repetitive automated checks without risking live operations. A build environment is focused on compiling/packaging and basic verification, not business acceptance. An integration environment is used to validate interactions among components/systems, but may not reflect full production- like configuration, and it's often shared and volatile-less suitable for formal acceptance activities involving end users. Production is generally avoided for UAT because acceptance testing can alter live data, disrupt users, and introduce unacceptable business risk; production testing is typically limited to tightly controlled smoke checks, monitoring, or specific "in-production" validation patterns with strong safeguards. Therefore, the environment in which both end-user manual UAT and supporting automated routine scenarios are typically executed is the preproduction environment, aligning with TAE's guidance on balancing realism with risk containment.