HOME

TheInfoList




A structure is an arrangement and organization of interrelated elements in a material object or
system A system is a group of Interaction, interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its environment, is described by its boundaries, structure and purp ...

system
, or the object or system so organized. Material structures include man-made objects such as
building A building, or edifice, is a structure with a roof and walls standing more or less permanently in one place, such as a house or factory. Buildings come in a variety of sizes, shapes, and functions, and have been adapted throughout history for a ...

building
s and
machine A machine is any physical system with ordered structural and functional properties. It may represent human-made or naturally occurring device molecular machine that uses Power (physics), power to apply Force, forces and control Motion, moveme ...

machine
s and natural objects such as
biological organisms
biological organisms
,
mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. (2 ...

mineral
s and
chemicals A chemical substance is a form of matter In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which ...
. Abstract structures include
data structure In computer science Computer science deals with the theoretical foundations of information, algorithms and the architectures of its computation as well as practical techniques for their application. Computer science is the study of ...

data structure
s in
computer science Computer science deals with the theoretical foundations of information, algorithms and the architectures of its computation as well as practical techniques for their application. Computer science is the study of computation, automation, a ...
and
musical form In music, form refers to the structure of a musical composition or performance. In his book, ''Worlds of Music'', Jeff Todd Titon suggests that a number of organizational elements may determine the formal structure of a piece of music, such as "th ...
. Types of structure include a
hierarchy A hierarchy (from the Greek: , from , 'president of sacred rites') is an arrangement of items (objects, names, values, categories, etc.) in which the items are represented as being "above", "below", or "at the same level as" one another. Hierarch ...

hierarchy
(a cascade of one-to-many relationships), a
network Network, networking and networked may refer to: Science and technology * Network theory Network theory is the study of Graph (discrete mathematics), graphs as a representation of either symmetric relations or directed graph, asymmetric relat ...
featuring many-to-many
link #REDIRECT Link Link or Links may refer to: Places * Link, West Virginia, an unincorporated community in the US * Link River, Klamath Falls, Oregon, US People with the name * Link (singer) (Lincoln Browder, born 1964), American R&B singer * L ...
s, or a lattice featuring connections between components that are neighbors in space.


Load-bearing

Building A building, or edifice, is a structure with a roof and walls standing more or less permanently in one place, such as a house or factory. Buildings come in a variety of sizes, shapes, and functions, and have been adapted throughout history for a ...

Building
s,
aircraft An aircraft is a vehicle that is able to flight, fly by gaining support from the Atmosphere of Earth, air. It counters the force of gravity by using either Buoyancy, static lift or by using the Lift (force), dynamic lift of an airfoil, or in ...

aircraft
,
skeleton A skeleton is a structural frame that supports an animal Animals (also called Metazoa) are multicellular eukaryotic organisms that form the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consu ...

skeleton
s,
anthills
anthills
,
beaver dam Beaver dams or beaver impoundments are dam A dam is a barrier that stops or restricts the flow of surface water An example of surface water is Lake Kinney. Surface water is water Water is an Inorganic compound, inorganic, T ...

beaver dam
s,
bridge A bridge is a Nonbuilding structure, structure built to Span (engineering), span a physical obstacle, such as a body of water, valley, or road, without closing the way underneath. It is constructed for the purpose of providing passage over the ...

bridge
s and
salt dome A salt dome is a type of structural dome formed when salt (or other evaporite evaporated from the Dead Sea, Israel Evaporite () is the term for a water-soluble mineral sediment Sediment is a naturally occurring material that is broken d ...
s are all examples of
load Load or LOAD may refer to: Aeronautics and transportation *Load factor (aeronautics), the ratio of the lift of an aircraft to its weight *Passenger load factor, the ratio of revenue passenger miles to available seat miles of a particular transpor ...
-bearing structures. The results of
construction Construction is a general term meaning the and to form , , or ,"Construction" def. 1.a. 1.b. and 1.c. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) Oxford University Press 2009 and comes from ''constructio'' (from ''com-' ...

construction
are divided into
building A building, or edifice, is a structure with a roof and walls standing more or less permanently in one place, such as a house or factory. Buildings come in a variety of sizes, shapes, and functions, and have been adapted throughout history for a ...

building
s and
non-building structure A nonbuilding structure, also referred to simply as a structure, refers to any body or system of connected parts used to support a load that was not designed for continuous human occupancy Within the context of building construction and build ...
s, and make up the
infrastructure Infrastructure is the set of fundamental facilities and systems that support the sustainable functionality of households and firms. Serving a country, city, or other area, including the services and facilities necessary for its economy An eco ...

infrastructure
of a human society. Built structures are broadly divided by their varying design approaches and standards, into
categories Category, plural categories, may refer to: Philosophy and general uses *Categorization Categorization is the human ability and activity of recognizing shared features or similarities between the elements of the experience of the world (such ...
including building structures,
architectural structure Architectural engineering, also known as building engineering or architecture engineering, is an engineering discipline that deals with the technological aspects and multi-disciplinary Interdisciplinarity or interdisciplinary studies involves ...
s, civil engineering structures and mechanical structures. The effects of loads on physical structures are determined through
structural analysis Structural analysis is the determination of the effects of load Load or LOAD may refer to: Aeronautics and transportation *Load factor (aeronautics), the ratio of the lift of an aircraft to its weight *Passenger load factor, the ratio of reve ...
, which is one of the tasks of
structural engineering Structural engineering is a sub-discipline of in which s are trained to design the 'bones and muscles' that create the form and shape of man-made structures. also must understand and calculate the , strength, and earthquake-susceptibility of ...
. The structural elements can be classified as one-dimensional (
rope A rope is a group of yarns, Plying, plies, fibers or strands that are twisted or braided together into a larger and stronger form. Ropes have tensile strength and so can be used for dragging and lifting. Rope is thicker and stronger than simil ...

rope
s,
strut A strut is a structural component commonly found in engineering Engineering is the use of scientific principles to design and build machines, structures, and other items, including bridges, tunnels, roads, vehicles, and buildings. The d ...

strut
s, beams,
arch An arch is a vertical curved structure A structure is an arrangement and organization of interrelated elements in a material object or system A system is a group of Interaction, interacting or interrelated elements that act according to ...

arch
es), two-dimensional (
membrane A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Biological membranes include cell membranes (outer coverings of cells or organelles that all ...

membrane
s, plates,
slab Slab or SLAB may refer to: Physical materials * Concrete slab, a flat concrete plate used in construction * Stone slab, a flat stone used in construction * Slab (casting), a length of metal * Slab (geology), that portion of a tectonic plate that is ...

slab
,
shells Shell may refer to: Architecture and design * Shell (structure), a thin structure **Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses **Thin-shell structure, **Oil company Science Biology * Seashell ...
, vaults), or three-dimensional (solid masses). Three-dimensional elements were the main option available to early structures such as
Chichen Itza Chichen Itza , es, Chichén Itzá , often with the emphasis reversed in English to ; from yua, Chiʼchʼèen Ìitshaʼ () "at the mouth of the well of the people" was a large built by the of the Terminal Classic period. The is located ...

Chichen Itza
. A one-dimensional element has one dimension much larger than the other two, so the other dimensions can be neglected in calculations; however, the ratio of the smaller dimensions and the composition can determine the flexural and
compressive In continuum mechanics, stress is a physical quantity that expresses the internal forces that neighbouring particles of a continuous material exert on each other, while deformation (mechanics)#Strain, strain is the measure of the deformation of ...
stiffness of the element. Two-dimensional elements with a thin third dimension have little of either but can resist biaxial traction. The structure elements are combined in ''structural systems''. The majority of everyday load-bearing structures are ''section-active'' structures like frames, which are primarily composed of one-dimensional (bending) structures. Other types are ''Vector-active'' structures such as
truss A truss is an assembly of ''members'' such as beams, connected by ''nodes'', that creates a rigid structure. In engineering, a truss is a structure A structure is an arrangement and organization of interrelated elements in a material object ...

truss
es, ''surface-active'' structures such as shells and folded plates, ''form-active'' structures such as cable or membrane structures, and hybrid structures. Load-bearing biological structures such as bones, teeth, shells, and tendons derive their strength from a multilevel hierarchy of structures employing biominerals and
protein Proteins are large biomolecule , showing alpha helices, represented by ribbons. This poten was the first to have its suckture solved by X-ray crystallography by Max Perutz and Sir John Cowdery Kendrew in 1958, for which they received a No ...

protein
s, at the bottom of which are
collagen fibrils upright=1.5, Tropocollagen molecule: three left-handed procollagens (red, green, blue) join to form a right-handed triple helical tropocollagen. Collagen () is the main structural protein Proteins are large biomolecules or macromolecules that ...

collagen fibrils
.


Biological

In
biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemical processes, Molecular biology, molecular interactions, Physiology, physiological mechanisms, Development ...

biology
, one of the properties of
life Life is a characteristic that distinguishes physical entities A bubble of exhaled gas in water In common usage and classical mechanics, a physical object or physical body (or simply an object or body) is a collection of matter within a ...

life
is its highly ''ordered'' structure, which can be observed at multiple levels such as in cells,
tissue Tissue may refer to: Biology * Tissue (biology), an ensemble of similar cells that together carry out a specific function * ''Triphosa haesitata'', a species of geometer moth found in North America * ''Triphosa dubitata'', a species of geometer mot ...
s,
organ Organ may refer to: Biology * Organ (anatomy) An organ is a group of Tissue (biology), tissues with similar functions. Plant life and animal life rely on many organs that co-exist in organ systems. A given organ's tissues can be broadly cate ...
s, and
organism In biology Biology is the natural science that studies life and living organisms, including their anatomy, physical structure, Biochemistry, chemical processes, Molecular biology, molecular interactions, Physiology, physiological ...

organism
s. In another context, structure can also observed in
macromolecule A macromolecule is a very large molecule A molecule is an electrically Electricity is the set of physical phenomena associated with the presence and motion Image:Leaving Yongsan Station.jpg, 300px, Motion involves a change in ...
s, particularly
protein Proteins are large biomolecule , showing alpha helices, represented by ribbons. This poten was the first to have its suckture solved by X-ray crystallography by Max Perutz and Sir John Cowdery Kendrew in 1958, for which they received a No ...

protein
s and
nucleic acid Nucleic acids are biopolymer Biopolymers are natural polymer A polymer (; Greek ''wikt:poly-, poly-'', "many" + ''wikt:-mer, -mer'', "part") is a Chemical substance, substance or material consisting of very large molecules, or macromolecule ...

nucleic acid
s. The function of these molecules is determined by their shape as well as their composition, and their structure has multiple levels.
Protein structure Protein structure is the three-dimensional arrangement of atoms in an amino acid Amino acids are organic compound In , organic compounds are generally any s that contain - . Due to carbon's ability to (form chains with other carbon ...

Protein structure
has a four-level hierarchy. The ''
primary structure Biomolecular structure is the intricate folded, three-dimensional shape that is formed by a molecule File:Pentacene on Ni(111) STM.jpg, A scanning tunneling microscopy image of pentacene molecules, which consist of linear chains of five carbon ...

primary structure
'' is the sequence of
amino acid Amino acids are organic compound In , organic compounds are generally any s that contain - . Due to carbon's ability to (form chains with other carbon s), millions of organic compounds are known. The study of the properties, reactions, a ...

amino acid
s that make it up. It has a
peptide Peptides (from Greek language Greek ( el, label=Modern Greek Modern Greek (, , or , ''Kiní Neoellinikí Glóssa''), generally referred to by speakers simply as Greek (, ), refers collectively to the dialects of the Greek language spoken ...
backbone made up of a repeated sequence of a nitrogen and two carbon atoms. The ''
secondary structure Biomolecular structure is the intricate folded, three-dimensional shape that is formed by a molecule A scanning tunneling microscopy image of pentacene molecules, which consist of linear chains of five carbon rings. A molecule is an elect ...
'' consists of repeated patterns determined by
hydrogen bonding A hydrogen bond (or H-bond) is a primarily Electrostatics, electrostatic force of attraction between a hydrogen Hydrogen is the chemical element Image:Simple Periodic Table Chart-blocks.svg, 400px, Periodic table, The periodic table of ...
. The two basic types are the
α-helix The alpha helix (α-helix) is a common structural motif, motif in the Protein secondary structure, secondary structure of proteins and is a Screw thread#Handedness, right hand-helix conformation in which every backbone amino, N−H group hydrogen b ...

α-helix
and the β-pleated sheet. The ''
tertiary structure Biomolecular structure is the intricate folded, three-dimensional shape that is formed by a molecule A scanning tunneling microscopy image of pentacene molecules, which consist of linear chains of five carbon rings. A molecule is an elect ...
'' is a back and forth bending of the polypeptide chain, and the ''
quaternary structure Biomolecular structure is the intricate folded, three-dimensional shape that is formed by a molecule File:Pentacene on Ni(111) STM.jpg, A scanning tunneling microscopy image of pentacene molecules, which consist of linear chains of five carbon ...
'' is the way that tertiary units come together and interact. Structural biology is concerned with
biomolecular structure Biomolecular structure is the intricate folded, three-dimensional shape that is formed by a molecule A molecule is an electrically Electricity is the set of physical phenomena associated with the presence and motion Image:Leavin ...
of macromolecules.


Chemical

Chemical structure refers to both molecular geometry and electronic structure. The structure can be represented by a variety of diagrams called
structural formula The structural formula of a chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entity, molecular entities) composed of atoms from more than one chemical element, element held toge ...
s.
Lewis structure#REDIRECT Lewis structure Lewis structures, also known as Lewis dot formulas, Lewis dot structures, electron dot structures, or Lewis electron dot structures (LEDS), are diagrams that show the bonding between atom An atom is the smallest unit o ...
s use a dot notation to represent the
valence electron In chemistry Chemistry is the study of the properties and behavior of . It is a that covers the that make up matter to the composed of s, s and s: their composition, structure, properties, behavior and the changes they undergo during ...
s for an atom; these are the electrons that determine the role of the atom in chemical reactions. Bonds between atoms can be represented by lines with one line for each pair of electrons that is shared. In a simplified version of such a diagram, called a
skeletal formula The skeletal formula, also called line-angle formula or shorthand formula, of an organic compound In chemistry Chemistry is the study of the properties and behavior of . It is a that covers the that make up matter to the composed ...
, only carbon-carbon bonds and functional groups are shown. Atoms in a crystal have a
structure A structure is an arrangement and organization of interrelated elements in a material object or system A system is a group of Interaction, interacting or interrelated elements that act according to a set of rules to form a unified whole. ...

structure
that involves repetition of a basic unit called a ''unit cell''. The atoms can be modeled as points on a lattice, and one can explore the effect of
symmetry Symmetry (from Greek#REDIRECT Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the Hellenic Republic, is a country located in Southeast Europe. Its population is appro ...

symmetry
operations that include rotations about a point, reflections about a symmetry planes, and ''
translations Translation is the communication of the meaning of a source-language text by means of an equivalent target-language text. The English language draws a terminological distinction (which does not exist in every language) between ''transla ...
'' (movements of all the points by the same amount). Each crystal has a finite group, called the
space group In mathematics Mathematics (from Greek: ) includes the study of such topics as numbers (arithmetic and number theory), formulas and related structures (algebra), shapes and spaces in which they are contained (geometry), and quantities and ...
, of such operations that map it onto itself; there are 230 possible space groups. By Neumann's law, the symmetry of a crystal determines what physical properties, including
piezoelectricity Piezoelectricity (, ) is the electric charge Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field. Electric charge can be ''positive'' or ''negative'' (commonly carrie ...

piezoelectricity
and
ferromagnetism Ferromagnetism is the basic mechanism by which certain materials (such as iron Iron () is a chemical element with Symbol (chemistry), symbol Fe (from la, Wikt:ferrum, ferrum) and atomic number 26. It is a metal that belongs to the first tr ...
, the crystal can have.


Mathematical


Musical

A large part of
numerical analysis Numerical analysis is the study of algorithms that use numerical approximation (as opposed to symbolic computation, symbolic manipulations) for the problems of mathematical analysis (as distinguished from discrete mathematics). Numerical analysis ...
involves identifying and interpreting the structure of musical works. Structure can be found at the level of part of a work, the entire work, or a group of works. Elements of music such as
pitch Pitch may refer to: Acoustic frequency * Pitch (music), the perceived frequency of sound including "definite pitch" and "indefinite pitch" ** Absolute pitch or "perfect pitch" ** Pitch class, a set of all pitches that are a whole number of octaves ...
,
duration Duration may refer to: * The amount of Time#Terminology, time elapsed between two events * Duration (music) – an amount of time or a particular time interval, often cited as one of the fundamental aspects of music * Duration (philosophy) – a th ...
and
timbre In music, timbre ( ), also known as tone color or tone quality (from psychoacoustics Psychoacoustics is the branch of psychophysics Psychophysics quantitatively investigates the relationship between physical stimulus (physiology), stimuli a ...

timbre
combine into small elements like motifs and
phrases In everyday speech, a phrase is any group of words, often carrying a special idiomatic meaning; in this sense it is synonymous with expression. In linguistic analysis, a phrase is a group of words (or possibly a single word) that functions as a c ...
, and these in turn combine in larger structures. Not all music (for example, that of
John Cage John Milton Cage Jr. (September 5, 1912 – August 12, 1992) was an American composer A composer (Latin wikt:compono, ''compōnō''; literally "one who puts together") is a person who writes musical composition, music, especially classical ...
) has a
hierarchical organization A hierarchical organization is an organizational structure where every entity in the organization An organization, or organisation ( Commonwealth English; see spelling differences), is an entity – such as a company, an institution, or ...
, but hierarchy makes it easier for a listener to understand and remember the music. In analogy to
linguistic Linguistics is the scientific study of language A language is a structured system of communication Communication (from Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo ...

linguistic
terminology, motifs and phrases can be combined to make complete musical ideas such as
sentences ''The Four Books of Sentences'' (''Libri Quattuor Sententiarum'') is a book of theology Theology is the systematic study of the nature of the Divinity, divine and, more broadly, of religious belief. It is taught as an Discipline (academia), aca ...
and
phrases In everyday speech, a phrase is any group of words, often carrying a special idiomatic meaning; in this sense it is synonymous with expression. In linguistic analysis, a phrase is a group of words (or possibly a single word) that functions as a c ...
. A larger form is known as the
period Period may refer to: Common uses * Era, a length or span of time * Full stop (or period), a punctuation mark Arts, entertainment, and media * Period (music), a concept in musical composition * Period, a descriptor for a historical or period drama ...
. One such form that was widely used between 1600 and 1900 has two phrases, an ''antecedent'' and a ''consequent'', with a half
cadence In Western musical theory, a cadence (Latin ''cadentia'', "a falling") is "a melodic or harmonic configuration that creates a sense of resolution inality or pause.Don Michael Randel (1999). ''The Harvard Concise Dictionary of Music and Musician ...
in the middle and a full cadence at the end providing punctuation. On a larger scale are single-movement forms such as the
sonata form Sonata form (also ''sonata-allegro form'' or ''first movement form'') is a musical form, musical structure generally consisting of three main sections: an exposition, a development, and a recapitulation. It has been used widely since the middl ...
and the , and multi-movement forms such as the
symphony A symphony is an extended musical composition Musical composition can refer to an Originality, original piece or work of music, either Human voice, vocal or Musical instrument, instrumental, the musical form, structure of a musical piece ...

symphony
.


Social

A social structure is a pattern of relationships. They are social
organization An organization, or organisation (Commonwealth English The use of the English language English is a of the , originally spoken by the inhabitants of . It is named after the , one of the ancient that migrated from , a peninsu ...

organization
s of individuals in various life situations. Structures are applicable to people in how a society is as a system organized by a characteristic pattern of relationships. This is known as the social organization of the group. Sociologists have studied the changing structure of these groups.
Structure and agency In the social science Social science is the branch The branches and leaves of a tree. A branch ( or , ) or tree branch (sometimes referred to in botany Botany, also called , plant biology or phytology, is the science of plant l ...
are two confronted theories about human behaviour. The debate surrounding the influence of structure and agency on human thought is one of the central issues in sociology. In this context, ''agency'' refers to the individual human capacity to act independently and make free choices. ''Structure'' here refers to factors such as
social class A social class is a set of concepts in the social sciences Social science is the Branches of science, branch of science devoted to the study of society, societies and the Social relation, relationships among individuals within those soc ...
,
religion Religion is a social Social organisms, including humans, live collectively in interacting populations. This interaction is considered social whether they are aware of it or not, and whether the exchange is voluntary/involuntary. Etymology ...

religion
,
gender Gender is the range of characteristics pertaining to, and differentiating between femininity Femininity (also called womanliness or girlishness) is a set of attributes, behaviors, and roles generally associated with women A woman is ...

gender
,
ethnicity An ethnic group or ethnicity is a grouping of people A people is any plurality of persons considered as a whole. Used in politics and law it is a term to refer to the collective or community of an ethnic group, a nation, to the public or ...
, customs, etc. that seem to limit or influence individual opportunities.


Data

In
computer science Computer science deals with the theoretical foundations of information, algorithms and the architectures of its computation as well as practical techniques for their application. Computer science is the study of computation, automation, a ...
, a data structure is a way of organizing information in a
computer A computer is a machine that can be programmed to Execution (computing), carry out sequences of arithmetic or logical operations automatically. Modern computers can perform generic sets of operations known as Computer program, programs. These ...

computer
so that it can be used efficiently. Data structures are built out of two basic types: An
array ARRAY, also known as ARRAY Now, is an independent distribution company launched by film maker and former publicist Ava DuVernay Ava Marie DuVernay (; born August 24, 1972) is an American filmmaker. She won the directing award in the U.S. dram ...
has an index that can be used for immediate access to any data item (some
programming language A programming language is a formal language In logic, mathematics, computer science, and linguistics, a formal language consists of string (computer science), words whose symbol (formal), letters are taken from an alphabet (computer science) ...

programming language
s require array size to be initialized). A
linked list In computer science Computer science deals with the theoretical foundations of information, algorithms and the architectures of its computation as well as practical techniques for their application. Computer science is the study of , ...

linked list
can be reorganized, grown or shrunk, but its elements must be accessed with a pointer that links them together in a particular order. Out of these any number of other data structures can be created such as stacks, queues,
trees In botany Botany, also called , plant biology or phytology, is the science Science (from the Latin word ''scientia'', meaning "knowledge") is a systematic enterprise that Scientific method, builds and Taxonomy (general), organiz ...
and
hash table In computing Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentation of algorithmic processes and development of both computer hardware , hardware and ...
s. In solving a problem, a data structure is generally an integral part of the
algorithm In and , an algorithm () is a finite sequence of , computer-implementable instructions, typically to solve a class of problems or to perform a computation. Algorithms are always and are used as specifications for performing s, , , and other ...

algorithm
. In modern programming style, algorithms and data structures are encapsulated together in an
abstract data type In computer science Computer science deals with the theoretical foundations of information, algorithms and the architectures of its computation as well as practical techniques for their application. Computer science is the study of , ...
.


Software

Software architecture is the specific choices made between possible alternatives within a framework. For example, a framework might require a database and the architecture would specify the type and manufacturer of the database. The
structure A structure is an arrangement and organization of interrelated elements in a material object or system A system is a group of Interaction, interacting or interrelated elements that act according to a set of rules to form a unified whole. ...
of software is the way in which it is partitioned into interrelated components. A key structural issue is minimizing dependencies between these components. This makes it possible to change one component without requiring changes in others. The purpose of structure is to optimise for (brevity, readability, traceability, isolation and encapsulation, maintainability, extensibility, performance and efficiency), examples being: language choice,
code In communication Communication (from Latin Latin (, or , ) is a classical language A classical language is a language A language is a structured system of communication Communication (from Latin ''communicare'', mean ...
,
functions Function or functionality may refer to: Computing * Function key A function key is a key on a computer A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations automatically. Modern comp ...

functions
,
libraries A library is a collection of materials, books or media that are easily accessible for use and not just for display purposes. It is responsible for housing updated information in order to meet the user's needs on a daily basis. A library provi ...
, builds, system evolution, or diagrams for flow logic and
design A design is a plan or specification for the construction of an object or system or for the implementation of an activity or process, or the result of that plan or specification in the form of a prototype A prototype is an early sample, mode ...
. Structural elements reflect the requirements of the application: for example, if the system requires a high fault tolerance, then a redundant structure is needed so that if a component fails it has backups. A high redundancy is an essential part of the design of several systems in the
Space Shuttle The Space Shuttle is a retired, partially reusable low Earth orbit A low Earth orbit (LEO) is an Earth-centered orbit near the planet, often specified as having a period Period may refer to: Common uses * Era, a length or span of time * ...

Space Shuttle
.


Logical

As a branch of philosophy,
logic Logic is an interdisciplinary field which studies truth and reasoning. Informal logic seeks to characterize Validity (logic), valid arguments informally, for instance by listing varieties of fallacies. Formal logic represents statements and ar ...

logic
is concerned with distinguishing good arguments from poor ones. A chief concern is with the structure of arguments. An argument consists of one or more
premise A premise or premiss is a true or false statement that helps form the body of an argument In logic Logic is an interdisciplinary field which studies truth and reasoning Reason is the capacity of consciously making sense of things, appl ...
s from which a conclusion is
inferred Inferences are steps in reasoning Reason is the capacity of consciously making sense of things, applying logic Logic (from Ancient Greek, Greek: grc, wikt:λογική, λογική, label=none, lit=possessed of reason, intellectual, di ...

inferred
. The steps in this inference can be expressed in a formal way and their structure analyzed. Two basic types of inference are deduction and
induction Induction may refer to: Philosophy * Inductive reasoning, in logic, inferences from particular cases to the general case Biology and chemistry * Labor induction (birth/pregnancy) * Induction chemotherapy, in medicine * Induction period, the t ...
. In a valid deduction, the conclusion necessarily follows from the premises, regardless of whether they are true or not. An invalid deduction contains some error in the analysis. An inductive argument claims that if the premises are true, the conclusion is likely.


See also

* Abstract structure *
Mathematical structure In mathematics Mathematics (from Ancient Greek, Greek: ) includes the study of such topics as quantity (number theory), mathematical structure, structure (algebra), space (geometry), and calculus, change (mathematical analysis, analysis). It ...
*
Structural geology Structural geology is the study of the three-dimensional distribution of rock Rock most often refers to: * Rock (geology) A rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by th ...
*
Structure (mathematical logic) In universal algebraUniversal algebra (sometimes called general algebra) is the field of mathematics that studies algebraic structures themselves, not examples ("models") of algebraic structures. For instance, rather than take particular Group (mat ...
*
Structuralism (philosophy of science) Structuralism (also known as scientific structuralism or as the structuralistic theory-concept) is an active research program in the philosophy of science, which was first developed in the late 1960s and throughout the 1970s by several analytic phil ...


References


Further reading

* * * *


External links

* (syllabus and reading list) {{Authority control Systems