White box (software engineering)

"Open box" redirects here. "Open box" is also the name of the visible symbol ␣ that is sometimes used to indicate a space. See whitespace character.

Not to be confused with White-box testing, White-box cryptography, or White box (computer hardware).

A white box (or glass box, clear box, or open box) is a subsystem whose internals can be viewed but usually not altered.^[1] The term is used in systems engineering, software engineering, and in intelligent user interface design,^[2][3] where it is closely related to recent interest in explainable artificial intelligence.^[4][5]

Black box systems
System
Black box, Oracle machine
Methods and techniques
Black-box testing, Blackboxing
Related techniques
Feed forward, Obfuscation, Pattern recognition, White box, White-box testing, Gray-box testing, System identification
Fundamentals
A priori information, Control systems, Open systems, Operations research, Thermodynamic systems
v t e

Having access to the subsystem internals in general makes the subsystem easier to understand, but also easier to hack; for example, if a programmer can examine source code, weaknesses in an algorithm are much easier to discover.^{[citation needed]} That makes white-box testing much more effective than black-box testing but considerably more difficult from the sophistication needed on the part of the tester to understand the subsystem.

The notion of a "Black Box in a Glass Box" was originally used as a metaphor for teaching complex topics to computing novices.^[6]

Mathematical models for complex systems

See also

• Black box
• Gray-box testing