Flowcharts

Introduction


What do technical communicators need to know about flowcharts? As the saying loosely goes, “a picture says a thousand words.” This fact, while cliché, bears weight for the technical communicator in practice. Throughout technical communications history, practitioners have paired their text with visual components to get ideas across and help their audiences parse complex processes, data, and information. Today, a growing, multimedia tool set is available to technical communicators: e.g., graphic creation, photo and video editing, interactive media, and so on. This wiki entry concentrates on the accepted standards and best practices of a small sub-set in the broader scope of information design[hyperlink to other wiki entry], the ubiquitous, highly effective, yet oft-misunderstood tool: the flowchart!

Technical communicators take note: Flowcharts are valuable tools, not only for visualizing, for example, a computer's schemata or an organization's business workflow processes, but they're also great for visualizing the actual writing process and the documentation flow of materials. With flowcharts, in other words, you harness a powerful visual tool-set that can be used throughout the communications process, both to chart others' documentation flows and your own.

Overview
A flowchart, at its most basic, is "a diagram using symbols, words, or pictures to show the stages of a process in sequence from beginning to end. A flowchart provides an overview of a process and allows the reader to identify its essential steps quickly and easily."

Types of Flowcharts
Flowcharts are a means to a variety of ends, and they come in all shapes and sizes. Flowcharts often pair text of varying length with images and symbols, but in some cases, the images and symbols can replace the text entirely. Below is a very simplistic conceptual breakdown of flowchart types, ending with the current International Organizations for Standardization (ISO) standards and best practices for Technical Communicators to be aware of.



Pictorial diagrams
Pictorial diagrams use symbols to demonstrate a process (sometimes with accompanying text, sometimes not). The use of pictures goes back to the earliest forms of step-by-step communications archaeologists know of (see History section), in which flowcharts are used to represent processes in the natural world. Today, pictorial diagrams are quite common and can be used to represent nearly any process, such as the life cycle shown in figure 1 below.





Block Diagrams
Representing processes organized into labeled rectangular blocks is another effective form of fluidly communicating complex flows, as shown in the example diagrams below.
 * The first example block diagram below is a figure from chapter 8 of iFixit's online Tech Writing Handbook. This particular flowchart maps out the process of removing various components of a computer in order to replace them, starting with the "Lower Case." The flowchart shows its audience, without needing to state in text, that after the "Lower Case," the "Battery" is the next component to remove before the "Display," "Air Port," "Fan," and "RAM."
 * The second figure below is a reliability diagram that uses the block diagram method to show how subsystems are dependent on one another.

These are just two of many examples that can be found. Nearly every process can be represented in a simple, yet visually effective, block diagram.

International Organizations for Standardization (ISO) Flowchart Symbols
In the 1960s, the American National Symbols Institute (ANSI) set standards for flowcharts and their symbols, which were then adopted by the International Organizations for Standardization (ISO) in 1970. The current standard was revised in 1985. ISO symbols are shown in figure 4 below, with a brief description of each component.



Start/End

Oval: The start and end of a process are referred to officially as terminals. As a general rule, their should always be a start and end to a flowchart (if the flowchart's end terminal doesn't reference another flowchart).

Process

Rectangle: Represents steps in the process, which generally includes a set of operations that change value, form, or location of data.

Input/Output

Parallelogram: Entering or creating/displaying data and/or information.

Decision: Yes/No?

Diamond/rhombus: Conditional operation determining which of two paths the program will take. Can also be "True" and "False," and other similar concepts.

Sub-Process

Rectangle with double-struck edges: Named process which is defined elsewhere.

In-Process Reference

Circle: Pairs of labeled connectors replace long or confusing lines on a flowchart page. Represented by a small circle with a letter inside.

Out-of-Process Reference

Pentagon "home plate": A labeled connector for use when the target is on another page.

Annotation

Open rectangle: Additional information about a step the program.

Flow-line

Line (often arrow-headed): Shows the process's order of operation, often with an arrowhead. A line coming from one symbol and ending at another.

Flowchart Software
Today, there are several software applications than can be used to create flowcharts, including: The Microsoft (MS) Office Suite has several applications that can be used to create flowcharts. MS Visio is the specific program that MS designed for flowcharts, diagrams, and other visualizations, but MS PowerPoint, Word, and Excel can also be used.

Other software includes: Lucidchart and SmartDraw.

History
For those interested in the history of flowcharts, this topic is difficult to map. There is currently no comprehensive flowchart to the history of flowcharts. The following information in this section is not meant to be at all comprehensive. Technical Communicators interested in the history of flowcharts are encouraged to consult the references provided in this wiki entry for more information.

For the purposes of this wiki entry, the history of flowcharts is broken into two timelines:
 * Modern History
 * Prehistory

Modern History


The standard flowchart that Technical Communicators know and use today undeniably has its roots the rise of algorithmic theory in mechanical engineering. From the earliest days of the electronic computer, flowcharts have been used to represent the complex conceptual structures of hardware and software schemata.

The work that began the process of standardization under a comprehensive theory can be traced back to a 24-page paper published in the American Society of Mechanical Engineers (ASME) in 1921, a short set of lectures called "Process Charts," in which the husband-wife team Frank Gilbreth and Lillian Gilbreth introduced to society members and future readers their "first steps in finding the one best way to do work," which was essentially what would become the ASME Standard Operation and Flow Process Charts manual.

Flowcharts are said to have been popularized by Herman Goldstine and John von Neumann in the mid-1940s, see figure 6 below, and by the early 1960s, the flowchart was well established as an essential element of any large-scale software development project. By the early 1970s, the conventional wisdom was that “developing a program flowchart is a necessary first step in the preparation of a computer program.”



Prehistory
The use of visual imagery to convey a step-by-step process is so fundamental to Homo sapiens that its roots can be traced back to our ancient ancestors' earliest documentation, the well-known painted caves throughout of Europe and Asia, and as far as Australia and Indonesia. In these caves, archaeologists have found evidence of prehistoric process flows.

One of the most famous of these caves is called the "Volp complex," three interconnected subterranean caverns under the foothills of the Pyrenees named the "Cave of the Trois-Frères" for the three French brothers (trois frères) who were given attribution of rediscovering the cave. On the cave walls, hundreds of images of bison, bears, horses, reindeer, mammoths, stags, and other fauna are superimposed on top of one another. Often, these animals are drawn "in a kinetic blur suggesting motion." In one instance in which the superimposed tail of a bison-like animal can be seen to wag back and forth, left to right, step by step, when the superimposed images are set sequentially to one another, see figures 5.A and 5.B below.

Search Index Terms
Below are other terms related to flowchart:
 * Computers - Analysis
 * Computer Programming - Methods
 * Flowcharts - Analysis
 * Flowcharts - Flow diagram
 * Flowcharts - History
 * Flowcharts - Swimlane
 * Process mapping
 * Software Engineering - History
 * Systems Analysis