Natural science sciences, there are three great branches of "natural science" which stand apart by reason of the variety of far reaching deductions drawn from a small number of primary postulates — they are mechanics, electrodynamics, and thermodynamics. Today, natural sciences are more commonly divided into life sciences, such as botany and zoology; and physical sciences, which include physics, chemistry, geology, astronomy, and materials science. Natural science Natural science is a branch of science concerned with the description, prediction, and understanding of natural phenomena, based on empirical evidence from observation and experimentation. Mechanisms such as peer review and repeatability of findings are
Branches of science used in later efforts in other fields, such as the action theory of Alcott Parsons and the system-theory of Nickolas McLuhan. In this context the word "systems" is used to refer specifically to self-regulating systems, i.e. that are self-correcting through feedback. Self-regulating systems are found in nature, including the physiological systems of our body, in local and global ecosystems, and in climate. "Theoretical computer science" (TCS) is a division or subset of general computer science and focuses on more abstract or mathematical aspects of computing. These divisions and subsets include analysis of algorithms and formal semantics of programming languages. Technically,