Knowledge database software is not merely a list of documents, it is the foundation of the effective working process. Consider real time search that can comprehend human queries, security and permissions so that sensitive information is safe, analytics so that you know what people are searching and where you have gaps as well as how to integrate with your workflow tools that people use regularly. Lightweight tools are desired by small teams; scalability, support of many languages, and being able to work in groups are desired by large organizations. Fit (not over-paying, not under-scoping) may make the difference between the speed of your team learning and problem-solving.