A knowledge base (or knowledgebase; abbreviated KB, kb or ΔFact: date=January 2008) is a special kind of database for knowledge management. It provides the means for the computerized collection, organization, and retrieval of knowledge.

Just as it has become standard practice to write database as one word it is increasingly common - but grammatically incorrect - in computer science to write knowledgebase as one word (an interim approach was to write the term with a hyphen).

Types

Knowledge bases are categorized into two major types:

• Machine-readable knowledge bases store knowledge in a computer-readable form, usually for the purpose of having automated deductive reasoning applied to them. They contain a set of data, often in the form of rules that describe the knowledge in a logically consistent manner. Logical operators, such as And (conjunction), Or (disjunction), material implication and negation may be used to build it up from the atomic knowledge. Consequently, classical deduction can be used to reason about the knowledge in the knowledge base.

• Human-readable knowledge bases are designed to allow people to retrieve and use the knowledge they contain, primarily for training purposes. They are commonly used to capture explicit knowledge of an organization, including troubleshooting, articles, white papers, user manuals and others. A primary benefit of such a knowledge base is that it can help a user to find an existing solution to his or her current problem (thus avoiding having to 're-invent the wheel').

The most important aspect of a knowledge base is the quality of information it contains. The best knowledge bases have carefully written articles that are kept up to date, an excellent information retrieval system (such as a search engine), and a carefully designed content format and classification structure.

A knowledge base may use an ontology to specify its structure (entity types and relationships) and classification scheme. An ontology, together with a set of instances of its classes, constitutes a knowledge base.

Determining what type of information is captured, and where that information resides in a knowledge base, is something that is determined by the processes that support the system. A robust process structure is the backbone of any successful knowledge base.

Some knowledge bases have an artificial intelligence component. These kinds of knowledge bases can suggest solutions to problems sometimes based on feedback provided by the user, and are capable of learning from experience (see expert system). Knowledge representation, automated reasoning and argumentation are active areas of research at the forefront of artificial intelligence.