System Vs Acceptance testing

System testing

1. System testing is concerned with the behavior of the whole system/product as defined by the scope of a development project or product. It may include tests based on risks and/or requirements specification, business processes, use cases, or other high level descriptions of system behavior, interactions with the operating system, and system resources

2. System testing is most often the final test on behalf of development to verify that the system to be delivered meets the specification and its purpose may be to find as many defects as possible. Most often it is carried out by specialist testers that form a dedicated, and sometimes independent, test team within development, reporting to the development manager or project manager. In some organizations system testing is carried out by a third party team or by business analysts.

3. System testing should investigate both functional and non-functional requirements (performance, load, security, usability, reliability) of the system.

Acceptance testing

1. When the development organization has performed its system test and has corrected all or most defects, the system will be delivered to the user or customer for acceptance testing. The acceptance test should answer questions such as: 'Can the system be released?', 'What, if any, are the outstanding (business) risks?' and 'Has development met their obligations?'.

2. Acceptance testing is most often the responsibility of the user or customer, although other stakeholders may be involved as well. The execution of the acceptance test requires a test environment that is for most aspects, representative of the production environment ('as-if production').

3. The goal of acceptance testing is to establish confidence in the system, part of the system or specific non-functional characteristics, e.g. usability, of the system. Acceptance testing is most often focused on a validation type of testing, whereby we are trying to determine whether the system is fit for purpose. Finding defects should not be the main focus in acceptance testing. Although it assesses the system's readiness for deployment and use, it is not necessarily the final level of testing

4. Types of Acceptance testing:

- Alpha testing takes place at the developer's site. A cross-section of potential users and members of the developer's organization are invited to use the system. Developers observe the users and note problems. Alpha testing may also be carried out by an independent test team.

- Beta testing, or field testing, sends the system to a cross-section of users who install it and use it under real-world working conditions. The users send records of incidents with the system to the development organization where the defects are repaired.

- Contract acceptance testing is performed against a contract's acceptance criteria for producing custom-developed software. Acceptance should be formally defined when the contract is agreed

- Compliance acceptance testing or regulation acceptance testing is performed against the regulations which must be adhered to, such as governmental, legal or safety regulations.