White box (software engineering) on:
[Wikipedia]
[Google]
[Amazon]
A white box (or glass box, clear box, or open box) is a 
subsystem
A system is a group of interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its environment, is described by its boundaries, structure and purpose and express ...
whose internals can be viewed but usually not altered.Patrick J. Driscoll, "Systems Thinking," in Gregory S. Parnell, Patrick J. Driscoll, and Dale L. Henderson (eds.), ''Decision Making in Systems Engineering and Management'', 2nd. ed., Hoboken, NJ: Wiley, 2011, 40. The term is used in systems engineering
Systems engineering is an interdisciplinary field of engineering and engineering management that focuses on how to design, integrate, and manage complex systems over their life cycles. At its core, systems engineering utilizes systems thinking ...
as well as in software engineering
Software engineering is a systematic engineering approach to software development.
A software engineer is a person who applies the principles of software engineering to design, develop, maintain, test, and evaluate computer software. The term '' ...
.
Having access to the subsystem internals in general makes the subsystem easier to understand, but also easier to hack
Hack may refer to:
Arts, entertainment, and media Games
* ''Hack'' (Unix video game), a 1984 roguelike video game
* ''.hack'' (video game series), a series of video games by the multimedia franchise ''.hack''
Music
* ''Hack'' (album), a 199 ...
; for example, if a programmer can examine source code, weaknesses in an algorithm are much easier to discover. That makes white-box testing
White-box testing (also known as clear box testing, glass box testing, transparent box testing, and structural testing) is a method of software testing that tests internal structures or workings of an application, as opposed to its functionality ...
much more effective than black-box testing
Black-box testing is a method of software testing that examines the functionality of an application without peering into its internal structures or workings. This method of test can be applied virtually to every level of software testing: unit, ...
but considerably more difficult from the sophistication needed on the part of the tester to understand the subsystem.
See also
*Black box
In science, computing, and engineering, a black box is a system which can be viewed in terms of its inputs and outputs (or transfer characteristics), without any knowledge of its internal workings. Its implementation is "opaque" (black). The te ...
* White-box cryptography
Obfuscation is the obscuring of the intended meaning of communication by making the message difficult to understand, usually with confusing and ambiguous language. The obfuscation might be either unintentional or intentional (although intent u ...
* White-box testing
White-box testing (also known as clear box testing, glass box testing, transparent box testing, and structural testing) is a method of software testing that tests internal structures or workings of an application, as opposed to its functionality ...
References
Software testing {{soft-eng-stub