Personal Knowbase is a freeform notes database application for Microsoft Windows.
Stored articles are retrieved using a scheme based on user-defined keywords.
This type of keyword-based system was based on the keyword systems used by common research databases of the 1990s, such as Knowledge Index and CompuServe's file library, and is similar to the keywords Index for a MS Help file.
In recent Internet usage, such keywords are now often referred to as metadata "tags".
Personal Knowbase is a portable application and can be installed directly onto a USB flash drive.