A simple flowchart representing a process for dealing with a non-functioninglamp.
Aflowchart is a type ofdiagram that represents aworkflow orprocess. A flowchart can also be defined as a diagrammatic representation of analgorithm, a step-by-step approach to solving a task.
The flowchart shows the steps as boxes of various kinds, and their order by connecting the boxes with arrows. This diagrammatic representation illustrates a solution model to a given problem. Flowcharts are used in analyzing, designing, documenting or managing a process or program in various fields.[1]
Flow diagram aC-stylefor loop, representing the following code:
for(i=0;i<5;i++) printf("*");
The loop will cause five asterisks to be printed.
Flowcharts are used to design and document simple processes or programs. Like other types of diagrams, they help visualize the process. Two of the many benefits are that flaws andbottlenecks may become apparent. Flowcharts typically use the following main symbols:
A process step, usually called anactivity, is denoted by a rectangular box.
A decision is usually denoted by a diamond.
A flowchart is described as "cross-functional" when the chart is divided into different vertical or horizontal parts, to describe the control of different organizational units. A symbol appearing in a particular part is within the control of that organizational unit. A cross-functional flowchart allows the author to correctly locate the responsibility for performing an action or making a decision, and to show the responsibility of each organizational unit for different parts of a single process.
Common alternative names include: flow chart, process flowchart, functional flowchart, process map, process chart, functional process chart, business process model, process model, processflow diagram,work flow diagram, business flow diagram. The terms "flowchart" and "flow chart" are used interchangeably.
The underlyinggraph structure of a flowchart is a flow graph, which abstracts away node types, their contents and other ancillary information.
The first structured method for documenting process flow, the "flow process chart", was introduced byFrank andLillian Gilbreth in the presentation "Process Charts: First Steps in Finding the One Best Way to do Work", to members of theAmerican Society of Mechanical Engineers (ASME) in 1921.[2] The Gilbreths' tools quickly found their way intoindustrial engineering curricula. In the early 1930s, an industrial engineer,Allan H. Mogensen began to train business people in the use of some of the tools of industrial engineering at his Work Simplification Conferences inLake Placid,New York.
Art Spinanger, a 1944 graduate ofMogensen's class, took the tools back toProcter and Gamble where he developed their Deliberate Methods Change Program.Ben S. Graham, another 1944 graduate, Director of Formcraft Engineering atStandard Register Industrial, applied the flow process chart to information processing with his development of the multi-flow process chart, to present multiple documents and their relationships.[3] In 1947,ASME adopted a symbol set derived from Gilbreth's original work as the "ASME Standard: Operation and Flow Process Charts."[4]
Douglas Hartree in 1949 explained thatHerman Goldstine andJohn von Neumann had developed a flowchart (originally, diagram) to plan computer programs.[5] His contemporary account was endorsed by IBM engineers[6] and by Goldstine's personal recollections.[7] The original programming flowcharts of Goldstine and von Neumann can be found in their unpublished report, "Planning and coding of problems for an electronic computing instrument, Part II, Volume 1" (1947), which is reproduced in von Neumann's collected works.[8]
Sterneckert (2003) suggested that flowcharts can be modeled from the perspective of different user groups (such as managers, system analysts and clerks), and that there are four general types:[10]
Document flowcharts, showing controls over a document-flow through a system
Data flowcharts, showing controls over a data-flow in a system
System flowcharts, showing controls at a physical or resource level
Program flowchart, showing the controls in a program within a system
Notice that every type of flowchart focuses on some kind of control, rather than on the particular flow itself.[10]
However, there are some different classifications. For example, Andrew Veronis (1978) named three basic types of flowcharts: thesystem flowchart, thegeneral flowchart, and thedetailed flowchart.[11] That same year Marilyn Bohl (1978) stated "in practice, two kinds of flowcharts are used in solution planning:system flowcharts andprogram flowcharts...".[12] More recently, Mark A. Fryman (2001) identified more differences: "Decision flowcharts, logic flowcharts, systems flowcharts, product flowcharts, and process flowcharts are just a few of the different types of flowcharts that are used in business and government".[13]
In addition, many diagram techniques are similar to flowcharts but carry a different name, such asUMLactivity diagrams.
Reversible flowcharts[14] represent a paradigm in computing that focuses on the reversibility of computational processes. Unlike traditional computing models, where operations are often irreversible, reversible flowcharts ensure that any atomic computational step can be reversed. Reversible flowcharts are shown to be as expressive asreversible Turing machines, and are a theoretical foundation forstructured reversible programming and energy-efficient reversible computing systems.[15]
Shows the process's order of operation. A line coming from one symbol and pointing at another.[16] Arrowheads are added if the flow is not the standard top-to-bottom, left-to right.[17]
Indicates the beginning and ending of a program or sub-process. Represented as astadium,[16] oval or rounded (fillet) rectangle. They usually contain the word "Start" or "End", or another phrase signaling the start or end of a process, such as "submit inquiry" or "receive product".
Shows a conditional operation that determines which one of the two paths the program will take.[16] The operation is commonly a yes/no question or true/false test. Represented as a diamond (rhombus).[17]
Indicating additional information about a step in the program. Represented as an open rectangle with a dashed or solid line connecting it to the corresponding symbol in the flowchart.[17]
The ANSI/ISO standards include symbols beyond the basic shapes. Some are:[19][20]
Shape
Name
Description
Data File or Database
Data represented by acylinder symbolizing a disk drive.
Document
Single documents represented as arectangle with a wavy base.
Multiple documents represented as a stack of rectangles with wavy bases.
Manual operation
Represented by atrapezoid with the longest parallel side at the top, to represent an operation or adjustment to process that can only be made manually.
Manual input
Represented byquadrilateral, with the top irregularly sloping up from left to right, like the side view of akeyboard.
Preparation or Initialization
Represented by an elongatedhexagon, originally used for steps like setting a switch or initializing a routine.
Parallel Mode is represented by two horizontal lines at the beginning or ending of simultaneous operations[19]
Forparallel andconcurrent processing theParallel Mode horizontal lines[21] or a horizontal bar[22] indicate the start or end of a section of processes that can be done independently:
At afork, the process creates one or more additional processes, indicated by a bar with one incoming path and two or more outgoing paths.
At ajoin, two or more processes continue as a single process, indicated by a bar with several incoming paths and one outgoing path. All processes must complete before the single process continues.[22]
Any drawing program can be used to create flowchart diagrams, but these will have no underlying data model to share data with databases or other programs such asproject management systems orspreadsheet. Many software packages exist that can create flowcharts automatically, either directly from a programming language source code, or from a flowchart description language.
There are several applications andvisual programming languages[23] that use flowcharts to represent and execute programs. Generally these are used as teaching tools for beginner students.
^Gilbreth, Frank Bunker; Gilbreth, Lillian Moller (1921)."Process Charts"(PDF). Archived fromthe original(PDF) on 2015-05-09. Retrieved2016-05-06.. American Society of Mechanical Engineers.
^Graham, Ben S. Jr. (10 June 1996)."People come first".Keynote Address at Workflow Canada.
^American Society of Mechanical Engineers (1947)ASME standard; operation and flow process charts. New York, 1947. (online version)
^Jonathan W. Valvano (2011).Embedded Microcomputer Systems: Real Time Interfacing. Cengage Learning. pp. 131–132.ISBN978-1-111-42625-5.
^abRobbie T. Nakatsu (2009).Reasoning with Diagrams: Decision-Making and Problem-Solving with Diagrams. John Wiley & Sons. pp. 68–69.ISBN978-0-470-40072-2.
