  In the contemporary era, the importance of information is undisputed, but
there has never been a common understanding of information, nor a unanimous
conclusion to the researches on information metrics. Based on the previous
studies, this paper analyzes the important achievements in the researches of
the properties and metrics of information as well as their main
insufficiencies, and explores the essence and connotation, the mathematical
expressions and other basic problems related to information. On the basis of
the understanding of the objectivity of information, it proposes the
definitions and a Sextuple model of information; discusses the basic properties
of information, and brings forward the definitions and mathematical expressions
of nine kinds of metrics of information, i.e., extensity, detailedness,
sustainability, containability, delay, richness, distribution, validity and
matchability. Through these, this paper establishes a basic theory frame of
Objective Information Theory to support the analysis and research on
information and information system systematically and comprehensively.
