Acceptance testing is performed after system testing is done and all or most of the major defects have been fixed. The goal of acceptance testing is to establish confidence in the delivered software/system that it meets the end user/customers requirements and is fit for use Acceptance testing is done by user/customer and some of the project stakeholders.
Acceptance testing is done in production kind of environment.
For Commercial off the shelf (COTS) software’s that are meant for the mass market testing needs to be done by the potential users, there are two types of acceptance testing for COTS software’s.
Alpha testing is mostly applicable for software’s developed for mass market i.e. Commercial off the shelf(COTS), feedback is needed from potential users. Alpha testing is conducted at developers site, potential users, members or developers organization are invited to use the system and report defects.
Beta testing is also know as field testing, it is done by potential or existing users/customers at an external site without developers involvement, this test is done to determine that the software satisfies the end users/customers needs. This testing is done to acquire feedback from the market.