Branches of Science

Science refers to a body of knowledge, or a method of study devoted to developing this body of knowledge, concerning the nature of the universe gained through methodological observation and experimentation (scientific method). Exactly what constitutes science and scientific methods are subjects studied by the philosophy of science. The scientific method consists of various principles and procedures that are objective and repeatable by other scientists.

There are several ways of broadly categorizing the sciences, e.g. Pure science is systematic study of natural or physical phenomena by observation and experiment, critical testing and review, and ordering by general principles. Applied science is the search for practical uses of scientific knowledge; technology is the application of applied science.

Exact sciences are those which typically require precise measurements, such as physics, and to a lesser degree, chemistry. Descriptive sciences are those which are more oriented towards classification and description, such as biology and paleontology.

The pure natural sciences are typically divided into the physical sciences and the biological sciences, both of which can be subdivided. The major physical sciences are physics, astronomy, chemistry, and geology; the main biological sciences are botany and zoology.

The sciences aren’t distinct and independent from each other, but rather, there are are interconnections and cross-fertilisations. These interrelationships are often responsible for much of the progress today in several specialized fields of research, such as molecular biology and genetics. Several interdisciplinary sciences, such as biochemistry, have been created as a result.. Advances can be the result of research by teams of specialists representing different sciences, both pure and applied.

The Andromeda Galaxy


is the scientific study of objects in space: stars, planets, galaxies etc. Astronomy is the science dealing with all the celestial objects in the universe, including the planets and their satellites (e.g. our Earthand the moon), comets and meteors, the stars (including our sun), and interstellar matter, the star systems known as galaxies, and clusters of galaxies. Astronomers use telescopes (optical, radio, and others) to study stars, planets, and galaxies. Spacecraft carry telescopes and other astronomical instruments above the Earth‘s atmosphere, and to other planets in our solar system.

Radio Astronomy

is the study of the Universe and astrophysical phenomena, by examining their emission of electromagnetic radiation in the radio portion of the spectrum. Radio astronomy has greatly improved our understanding of the evolution of stars, the structure of galaxies, and the origin of the universe.


Questions concerning the nature of the Universe as a whole were until recently, the province of philosophy and superstition only. There was no way to examine the fabric of the heavens to see what it was made of – until the invention of spectroscopy and the construction of powerful telescopes in the past century. The data collected have been analysed with sophisticated mathematical techniques, and models have been developed which help us to understand how this Universemay have come to be how it is. Cosmologydraws on the physical sciences – especially mathematics, physics, and astronomy.

Biology and Life Sciences

The science and study of life, from the tiniest microscopic organisms to the largest whalesin the sea. Biology studies how living things grow, feed, move, reproduce, and evolve over long periods of time. It covers an enormous range of topics and deals with millions of species of animals, plants, and other organisms. To cope with this, biology is divided into several specialised branches such as anatomy (the structure of living things), and physiology (the way animals and plants function). Biology is useful to other sciences and professions that deal with life, such as agriculture, forestry, and medicine.

Because there is such a huge variety of living things on the earth, the science of biology has many different branches and areas of study and here you can find more details. Depending on their discipline, biologists usually research one or more of the following categories:

Microbiology, a study dealing with the structure and existence of microorganisms, which are tiny life forms such as a bacteria or a virus; Zoology, which is the study of animal life; Botany, which is focused on plant life; And physical anthropology, where scientists study human life, such as our existence and how we interact with other life forms.

Biologists also use other sciences to research life. Without chemistry and physics, much of the knowledge we have gathered about life would have been impossible to collect.

Woolly Mammoth


is the scientific study of life-forms existing in former geological time periods. When living things die they are sometimes buried in a layer of mud. After millions of years the mud turns into solid rock and the remains are preserved as fossils. The layers of rock can be dated, and so we know the age of the fossils in that layer. Paleontologists have discovered much about life that existed millions of years ago, by studying fossils. Especially interesting are the fossils of dinosaurs, some of which were very large indeed. Paleontologists know what they looked like and what they ate.

Periodic Table of Elements


is the study of the composition of substances and the changes that they undergo. In particular, chemistry is the study of elements(substances containing only one kind of atom) and the compounds (substances containing combined elements) they form. Chemists work with reactions between substances to create plastics, medicines, dyes, and many other materials useful in our modern world. They study what substances are made of, and how they can be altered or combined to create new materials. 92 elements occur in nature, and another 17 have been created in nuclear laboratories. Several million compounds have been synthesised by chemists.

There are two main divisions, organic and inorganic.

Organic chemistry originated with the isolation of medical compounds from animals and plants. It has expanded to include the reactions of carbon based compounds (which are 100 times more numerous than non-carbon based compounds) and the study of molecules.

Inorganic chemistry studies the preparation, properties, and reactions of all chemical elements and compounds except those that are carbon based.

Design of the Atom Created in a Lab at Columbia University


is the science of matter and energy, including light, sound, electricity, magnetism, radiation, and motion. Physics was once called natural philosophy, since it was “thoughts about the natural world”.

Physicists work with a mixture of theory and experiment. They perform experiments and try to construct theories to explain their results. These theories should make predictions which can be tested by new experiments. Those theories which have stood the test of time and have been especially useful are called the laws of physics.

Mathematics and Philosophy

Pencil Nub and Equation, 1951


- “the queen of the sciences” – deals with abstractions rather than observables, e.g. numbers, shapes, logic, size, structure, order, and other relationships among quantities. Some of the major branches are:

  • Arithmetic concerns addition, subtraction, multiplication, and division of numbers.
  • Algebra is a symbolic language in which problems can be solved using symbols to stand for varying or unknown quantities.
  • Geometry is the study of shapes and angles, and is useful in carpentry, architecture, and many other fields.

One of the commonest applications of mathematics to science is the use of equations to fit observed data, e.g. as in a graph of one quantity against another, such as temperature against time, for a cooling body.

School of Athens

Philosophy of Science

As used originally by the ancient Greeks, philosophy meant the pursuit of knowledge for its own sake.

Western philosophy is generally considered to have begun in ancient Greece as speculation about the underlying nature of the physical world. Philosophy comprised all areas of speculative thought and included the arts and sciences.

The philosophy of science seeks to clarify the objectives and means used by scientists, and what is the reliability of scientific theories.



Astronomy booksAstronomy is the science dealing with all the celestial objects in the universe, including the planets and their satellites (e.g. our Earth and the moon), comets and meteors, the stars (including our sun), and interstellar matter, the star systems known as galaxies, and clusters of galaxies.  Astrophysics, Cosmology, Galaxies, History, Radio, SETI, Solar, Stars, Telescope, UFO



Biology booksThe science of life and living organisms, biology studies the form, structure, function, growth and development, behavior and interaction of all living things. Biologists study the characteristics of life forms, such as their cellular organization and development, how they respond to stimulation, the chemical processes of their growth and production of energy (metabolism) and how they reproduce.  Biochemistry, Bioinformatics, Biophysics, Biotechnology, Botany, Cells, Ecology, Genetics, Human, Microbiology, Paleontology. Weiboto



Chemistry booksChemistry is the branch of science concerned with the properties, structure, and composition of substances and their reactions with one another. There are two main divisions, organic and inorganic. Chemical elements are the fundamental materials of which all matter is composed. An element is a pure substance that cannot be broken down or reduced further without changing its properties.  Analytical, Crystallography, Elements, Inorganic, Organic


History of Science

This article addresses modern science, by which we mean science as we now understand it; e.g. making use of the scientific method of controlled experimental verification of hypotheses. Before the 1500s, it was typically thought that the natural world could be understood by invoking supernatural deities, or by simplistic (and sometimes, not so simplistic) theories founded on casual observation and ‘common sense’ – e.g. that the Earth was the center of the Universe, because one could plainly see that the heavenly bodies (sun and planets) rotated about the Earth.



Mathematics booksMathematics is the study of numbers, sets of points, and various abstract elements, together with relations between them and operations performed on them. Originally mathematics was concerned with the properties of numbers and space, as the science of quantity, whether of magnitudes, as in geometry, or of numbers, as in arithmetic, or the generalization of these two fields, as in algebraAlgebra, Analysis, Applied, Calculus, Chaos, Fractals, Game Theory, Games, Geometry, Graphs, History, Infinity, Logic, Measurement, Number



Physics booksPhysics is the study of matter, energy, motion, and forces. Physics is a major branch of science, concerned with the fundamental components of the universe, the forces they exert on one another, and the results produced by these forces. Physicists study the properties and forms of matter and energy – heat, light, electricity and magnetism, and nuclear energy. They try to understand the forces that act in the universe, and the laws that these forces obey – e.g. matter and energy can’t be destroyed, only changed from one to the other (a conservation law).  Electricity, Light, Machines, Magnetism, Mechanics, Nuclear, Optics, Quantum, Relativity, Thermodynamics, Waves