(UAT) a work segment in the Testing Phase. It is the most comprehensive of all the testing work segments. It tests business functions and verifies the functional accuracy of programs, forms and procedures. It is planned and executed by a test team composed of project team members and functional area representatives.

In contrast to other forms of testing (which look for defects) user acceptance testing (of a built and tested system) seeks to show that a computer system is usable for people doing their normal work.

A series of tests carried out by an ‘end user' (person who your website is targeted at) to identify problems, issues or usability/functionality of a site either in production or on completion.

Formal testing conducted to enable a user, customer or other authorised entity to determine whether to accept a system or component.

A formal product evaluation performed by a customer as a condition of purchase.

User Acceptance Testing (UAT) is a process to obtain confirmation by a Subject Matter Expert (SME), preferably the owner or client of the object under test, through trial or review, that the modification or addition meets mutually agreed-upon requirements. In software development, UAT is one of the final stages of a project and often occurs before a client or customer accepts a new system.