Stephen Davies, Javier Velez-Morales, & Roger King (2005), "Building the memex sixty years later: trends and directions in personal knowledge bases", Department of Computer Science, University of Colorado at Boulder. The Wikipedia article on personal knowledge bases (PKBs) is basically a summary of the technical report. The report defined personal knowledge base systems, described their benefits, reviewed relevant fields of research, and compared systems in terms of several aspects of their data models: structural framework, knowledge elements, schema, and the role of transclusion. This report is the most comprehensive publication I've read that compares PKB systems according to their key features.

They should be well-organized and easy for customers to locate the information they need. 

More than anything, however, consumers want to find answers on their own. A study by Forrester confirmed that customers prefer knowledge bases over all other self-service channels. This is likely because the vast majority of customers want an immediate response to their customer service question — 90%, in fact.

A knowledge base is a self-serve online library of information about a product, service, department, or topic. 

A knowledge base (KB) is a technology used to store complex structured and unstructured information used by a computer system. The initial use of the term was in connection with expert systems; which were the first knowledge-based systems.