Being one of the most widely spread elements in existence, silicon throughout the history of human civilization played a very important role in architecture and construction, because it served as a component of many building materials, such as glass, concrete and stone. The most dramatic impact of silicon on the human existence and the world’s economics was caused, however, only in the 20th century, when it became widely used in the production of semiconductors and transistors that have later evolved into computer chips, laying a foundation for the whole information industry that is one of the most characteristic features of modern times.
An outliner (or "outline processor") is a specialized type of word processor used to view, create, build, modify, and maintain outlines. It is a computer program, or part of one, used for displaying, organizing, and editing hierarchically arranged text in an outline's tree structure . Textual information is contained in discrete sections called "nodes", which are arranged according to their topic-subtopic (parent-child) relationships, sort of like the members of a family tree . When loaded into an outliner, an outline may be collapsed or expanded to display as few or as many levels as desired.