Quality is delighting customers
Please find below answers to your queries from 'software testing services' point of view:
What is User Acceptance Testing?
UAT (User Acceptance Testing) means testing a software by the user/client to determine whether it can be accepted or not. They just specify the input to the system & check whether systems respond with correct result.
When it is to be done?
UAT is performed after System Testing is done and all or most of the major defects have been fixed. This testing is to be conducted in the final stage of Software Development Life Cycle (SDLC) prior to system being delivered to a live environment.
who will involve in this testing?
Such type of testing executed by client in separate environment (similar to production environment) & confirm whether system meets the requirements as per requirement specification or not. UAT users or end users are concentrating on end to end scenarios & typically involves running a suite of tests on the completed system.
Hope above details resolves your query.