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KMS is a direct descendant of ther ZOG research system developed at Carnegie Mellon University. KMS is an abbreviation for Knowledge Managment System and has been a commercial product since 1983. KMS is designed to manage fairly large hypertexts with many tens of thousands of nodes and has been designed from the start to work accross local area networks.
In contrast to Notecards KMS has a very simple data structure based on a single type of node called the frame. A frame can take over the entire workstation screen , but normally the screen is split into two frames each of which is about as big as a letter size page of paper. Users cannot mix small and large nodes and cannot have more than two nodes on the screen at the same time. This might seem limiting at first but proponents of KMS claim that it is much better to use the hypertext navigation mechanism to change the contents of the display than to use managment operation to help you find the desired information among ovelapping windows. Each frame may have six different functional parts : frame title, frame name , frame body, tree buttons, command buttons and annotation buttons. Frame title describes the frame topic. Frame name is a unique identifier for the topic. Frame body expands on the topic of the frame. Tree buttons link to frames at the lower level of the hierarchy. Command buttons initiate actions. annotation buttons begin with an "@" and provide notes or cross-references.
Navigation in KMS is done by clicking with the mouse on an anchor. KMS has been optimized for speen in navigation, so the destination frame will be displayed instantaneously as the user clicks the mouse on an anchor. The time to display a new frame is about half second and the designers of KMS claim that there is no real benefit to change the display to being faster than that. They experiment with display time in 0.05 seconds but it was so fast that users have problems noticing whether or not the screen has changed. If an item on the screen is not linked to another node , then clicking on it will generate an empty frame, making node and link creation seem like a special form of navigation to the user. It is also possible for a click to run a small programm written in the special KMS action language. The KMS user interface is based on the direct manipulation paradigm.
KMS does not provide an overview diagram but instead relies on fast navigation and a hierarchical structure of the nodes. Links across the hierarchy are prefixed with an "@" to let users know that thay are moving to another part of the information space.. Two additional facilities to help users navigate are the landmark status of the special "home" frame , which is directly accessible from any location , and the special ease and global availability of backtracking to the previous node by single clicking the mouse as long as it points to empty space on the screen. In addition to specifying within a frame the children of thet frame, KMS provides only one other view of the contents-a listing of the entire hierarchy of frame titles. There is no graphical browser. The outline of the database is not presented on the screen as a two dimensional graph. In early versions of KMS graphical views were available, but studies showed thet the graphical views were rarely used.
The source for a KMS link is an individual item in a frame. The destination for alink is a whole frame. A frame is considered to be a small unit that the whole frame, rather any part of it, can sensibly serve as the link destination. In KMS there are two types of links: tree and annotation. Tree links point to lower level frames in a hierarchy, such as a chapter of a book. Annotations point to peripheral material, such as comments. These two link types distinguish between structural relationships and purely associative relationships. Links may be more than one line text and allow the author to provide substantial semantic information about the link.