Online Technical Writing:
Graphics and Tables

One of the nice things about technical writing courses is that most of the papers have graphics in them � or at least they should. A lot of professional, technical writing contains graphics � drawings, diagrams, photographs, illustrations of all sorts, tables, pie charts, bar charts, line graphs, flow charts, and so on. Once you get the hang of putting graphics like these into your writing, you should consider yourself obligated to use graphics whenever the situation naturally would call for them.

Unlike what you might fear, producing graphics is not such a terrible task � in fact, it's fun. You don't have to be a professional graphics artist or technical draftsperson to produce graphics for your technical writing. There are ways to produce professional-looking graphics with tape, scissors, white-out, and a decent photocopying machine.

Graphics � an overview

Before getting into details on creating, formatting, and incorporating graphics, consider the types and their functions. You can use graphics to represent the following elements in your technical writing:

  • Objects � If you're describing a fuel-injection system, you'll probably need a drawing or diagram of the thing. If you are explaining how to graft a fruit tree, you'll need some illustrations of how that task is done. Photographs, drawings, diagrams, and schematics are the types of graphics that show objects.
  • Numbers � If you're discussing the rising cost of housing in Austin, you could use a table with the columns being for five-year periods since 1970; the rows could be for different types of housing. You could show the same data in the form of bar charts, pie charts, or line graphs. Tables, bar charts, pie charts, and line graphs are some of the principal ways to show numerical data.
  • Concepts � If you want to show how your company is organized, the relationships of the different departments and officials, you could set up an organization chart-boxes and circles connected with lines that show how everything is hierarchically arranged and related. This would be an example of a graphic for a concept: this type depicts nonphysical, conceptual things and their relationships.
  • Words � And finally graphics are used to depict words. You've probably noticed how textbooks put key definitions in a box, maybe with different color. The same can be done with key points or extended examples. Not the sexiest form of graphics, but it still qualifies, and it's good to keep in mind as a useful technique in certain situations.

Drawings, diagrams, photos

To depict objects, place, people and relationships between them, you can use photos, drawings, diagrams, and schematics.

Uses of illustrations and photos. In the realm of illustrations and photographs, the types run from minimal detail to maximal. A simple line drawing of how to graft a fruit tree reduces the detail to simple lines representing the hands, the tools, the graft stock, and graft. Diagrams are a more abstract, schematic view of things, for example, a wiring diagram of a clock radio; it hardly resembles the actual physical thing at all. And of course photographs provide the most detail of all. These graphics, supplying gradations of detail as they do, have their varying uses. Here are some examples:

  • In instructions, simple drawings (often called line drawings because they use just lines, without other detail such as shading) are the most common. They simplify the situation and the objects so that the reader can focus on the key details.
  • In descriptions, you would want to use drawings, but in this case drawings with more detail, such as shading and depth perspectives.
  • In feasibility, recommendation, and evaluation reports, photographs are often used. For example, if you are recommending a photocopier, you might want to include photos of the leading contenders.

Formatting requirements. When you use an illustration in a report, there are several requirements to keep in mind (most of these are shown in the schematic illustration):

  • Labels � Just about any illustration should contain labels � words and phrases � with pointers to the parts of the things being depicted.
  • Keys � If the illustration has certain shadings, colors, line styles, or other such details that have a special meaning in the illustration, these should be indicated in a key � an area in an unused corner of the illustration that deciphers their meaning.
  • Titles � Except in special cases, illustrations should have titles, and these titles should be numbered (Figure 1, Figure 2, and so on). The exceptions are these: if you have lots of illustrations (for example, in certain instructions, there are illustrations practically after every paragraph) and if there is no benefit from the titles; if you only have one or two illustrations and they are not cross-referenced; if you do not cross-reference your illustrations. In some of these cases, you might want to keep the title but discard the word "Figure" and the number following it.
  • Cross-references � Almost all illustrations should be referred to from the relevant point in the discussion. And, do more than just tossing in a "(See Figure 2.)"; discuss the illustration a bit � focus readers' attention on the key details of the illustration.
  • Location within the report � Ideally, you place illustrations just after the point where they are needed. However, sometimes because of the pagination (the way the text falls on the pages) and the size of the illustrations, this close placement is not possible. No problem � just put the illustration at the top of the next page; that is what the figure-numbering system is for.
  • Size of illustrations � Again, ideally, you want illustrations to be between one-half to one-quarter of the vertical size of the page. You want them to fit on the page with other text. In fact, that's what you really want � to interperse text and graphics in a report. What you do not want is to append the illustration to the back of the report! When you have a large illustration, use a photocopier to reduce it.
  • Placement within margins � Make sure that your illustrations fit neatly and comfortably within standard margins. You don't want the illustration spilling over into the right or left margins. You want to allow the equivalent of at least 2 blank lines above and below the illustration.
  • Level of technical detail � And, rather obviously, you want illustrations to be at the right technical level for your readers. No chip circuitry diagrams for computer beginners!

Producing illustrations. Now for the question we're all waiting to ask � how to create graphics? There are several options: photocopying, scanning, clip art, and hand-drawing. (And now most mainstream word-processing applications enable you to generate various kinds of graphs and charts, not to mention graphics and business software.) In all of these production methods, don't forget that you must indicate the source of the borrowed graphic.

  • Photocopying is the easiest solution to creating graphics � and it's legal (if you do it right)! Find the illustrations that you want, make good high-quality photocopies of them, trim off the figure titles and other unnecessary or inappropriate textual material (leave the labels and keys), and then leave space in your own document so that the trimmed photocopy will fit with at least 2 blank lines above and below it. Remember to reduce or enlarge the copy so that it fits nicely on the page. Also remember that ideal graphics are one-half to one-quarter the size of the page. Intersperse graphics with text! When you make the final copy of your document, tape in the copied graphics, photocopy the entire document, and hand in the photocopy (not the original).
  • Scanning is a neat way to pull graphics into your document files. You don't have to tape them to a copy then photocopy the document � they are there, fully integrated. However, there are some pretty cheap scanners that produce blurry, low-quality images. They're adequate for our technical writing course, but not for serious professional work.
  • Lots of clip art is becoming available with software programs and on the Internet. For fairly common objects such as computers, telephones, and such, you can insert these into your document and add labels to them.
  • Hand-drawing may not be as out of the question as you might think. Take a blank sheet of paper and start sketching lightly with a soft-leaded pencil. Keep working until you have the drawing the way you like. Then use a black marker to ink in the lines that you want, and erase the stray pencil markings. Now, treat this drawing the way you would any photocopied image. Cut it out, tape it in your document, photocopy it as well as all other pages, then hand in the photocopy.

See the discussion on indicating the source of borrowed information and the examples in the schematic illustration and table illustration.

Elements of a pictorial graphic. Notice that you can use a simpler means of indicating the source by using the same format as in regular number-system citations.


At least as the way things stand right now in the 1990s, getting photographs into reports is a problem. They don't photocopy well (although they do better now than just a few years ago). They don't attach to report pages very well either. High-quality scanning equipment may be the better alternative in this area, although a scanned image costs $5 to $10 right now at local copy shops equipped to offer this service. If you need to use photographs in your technical reports for a technical writing course, consult with your instructor. After all, these are writing courses, not graphic arts courses � taped-in or photocopied photographs may be okay in this setting.


Tables, of course, are those rows and columns of numbers and words, mostly numbers. They permit rapid access to and relatively easy comparison of information. If the data is arranged chronologically (for example, sales figures over a ten-year period), the table can show trends � patterns of rising or falling activity. Of course, tables are not necessarily the most vivid or dramatic means of showing such trends or relationships between data � that's why we have charts and graphs (discussed in the next section).

Uses for tables. The biggest use of tables is for numerical data. Imagine that you are comparing different models of laser printers in terms of physical characteristics such as height, depth, length, weight, and so on � perfect for a table.

However, don't get locked into the notion that tables are strictly for numerical data. Whenever you have situations where you discuss several things about which you provide the same categories of detail, you've got a possibility for a table. For example, imagine that you were comparing several models of a laser printer: you'd be saying the same category of thing about each printer (its cost, print speed, supply costs, warranty terms, and so on). This is ideal stuff for a table, and it would be mostly words rather than numbers (and in this case, you'd probably want to leave the textual discussion where it is and "re-present" the information in table form.

Table format. In its simplest form, a table is a group of rows and columns of data. At the top of each column is a column heading, which defines or identifies the contents of that column (and often it indicates the unit of measurement). On the left edge of the table may be row headings, which define or identify the contents of that row. Things get tricky when rows or columns must be grouped or subdivided. In such cases, you have to create row or column subheadings. This is illustrated in the table illustration.

Format for tables with grouped or subdivided rows and columns.

Traditionally, the title of a table is placed on top of the table or is the first row of the table. If the contents of the table are obvious and there is no need to cross-reference the table from anywhere else in the report, you can omit the title. To make life simpler, you can consider tables as figures (the same as illustrations and other graphics), and number them within the same sequence.

As for specific style and formatting guidelines for tables, keep these in mind (most of these guidelines are shown in the text-to-table illustration):

  • Refer to the table in the text just preceding the table. Explain the general significance of the data in the table; don't expect readers to figure it out entirely for themselves.
  • Don't overwhelm readers with monster 11-column, 30-row tables! Simplify the table data down to just that amount of data that illustrates your point � without of course distorting that data.
  • Don't put the word or abbreviation for the unit of measurement in every cell of a column. For example, in a column of measurements all in millimeters, don't put "mm" after every number. Put the abbreviation in parentheses in the column or row heading.
  • Right- or decimal-align numbers in the columns. If the 123 and 4 were in a column, the 4 would be right below the 3, not the 1.
  • Normally, words in columns are left-justified (although you will occasionally see columns of words all centered).
  • Column headings are centered over the columns of numerical data (forming a T-shape); left-aligned with columns of text. The alignment of column headings to the actual columnar data is variable. If you have a column of two- or three-letter words, you'd probably want to center the column heading over that data, even those it is words not numbers. (Doing so, avoids an odd-looking L-shaped column.)
  • When there is some special point you need to make about one or more of the items in the table, use a footnote instead of clogging up the table with the information.

Producing tables. Normally, you'll be borrowing information in which a good table occurs. If it's a simple table without too many rows and columns, retype it yourself into your own document (but remember to document where you borrowed it from in the figure title). However, if it is a big table with lots of data, you're justified in photopcopying it and bringing it into your report that way.

When you manually type tables, consider putting a string of hyphens between the column headings and the first row of data and another string of hyphens between the last row of data and any totals the table has.

Most of the advanced word-processing software packages, such as Word and WordPerfect, now have table-generating tools. You don't have to draw the lines and other formatting details.

Occasionally, in rough-draft technical reports, information is presented in regular running-text form that could be better presented in table (or tabular) form. Be sure and look back over your rough drafts for material that can transformed into tables.

For indicating the source of borrowed information, see the schematic illustration.

Format for tables. Watch for opportunities to convert text to table as in this example.

Charts and graphs

Charts and graphs are actually just another way of presenting the same data that is presented in tables � although a more dramatic and interesting one. At the same time, however, you get less detail or less precision in a chart or diagram than you do in the table. Imagine the difference between a table of sales figures for a ten-year period and a line graph for that same data. You get a better sense of the overall trend in the graph but not the precise dollar amount.

Formatting requirements. When you create charts and diagrams, keep these requirements in mind (most of these elements are illustrated below):

  • Axis labels � In bar charts and line graphs, don't forget to indicate what the x and y axes represent. One axis might indicate millions of dollars; the other, five-year segments from 1960 to the present.
  • Keys � Bar charts, line graphs, and pie charts often use special color, shading, or line style (solid or dashed). Be sure to indicate what these mean; translate them in a key (a box) in some unused place in the chart or graph.

Examples of graphs and charts. Notice the use of keys, axis labels, figure titles, and cross-references for both figures in this example.

  • Figure titles � For most charts and graphs, you'll want to include a title, in many cases, a numbered title. Readers need some way of knowing what they are looking at. And don't forget to cite the source of any information you borrowed in order to create the graphic. The standard rule for when to number figures or tables is this: if you cross-reference the figure or table elsewhere in the text.
  • Cross-references � Whenever you use a chart or graph, don't forget to put a cross-reference to it from the related text. With that cross-reference, provide some explanation of what is going on in the graphic, how to interpret it, what its basic trends are, and so on.
  • Documentation � When you borrow information to create a graphic, be sure to use the standard format to indicate the source. See the section on documenting borrowed information (either textual or graphic). It does not matter whether you photocopy the graphic and tape it into your report, retype the graphic (for example, a table), trace or draw the graphic freehand, or take some subset of the data (for example, using data from a table to create a bar chart) � it is all borrowed information, which some brave and noble soul worked hard to develop and who deserves credit for that effort.

Producing charts and graphs. As with illustrations, you have these options for creating charts and graphs: photocopying from other sources, generating your own with special software, and manual creating your own. Many of the text-processing software packages have fancy features for generating charts and graphs � you just crank in your data, specify the format you want, and let 'er rip.

Documenting graphics � indicating sources

As mentioned earlier, it's perfectly legal to borrow graphics � to trace, photocopy, scan, or extract subsets of data from them. But you're obligated to cite your sources for graphics just as you are for the words you borrow. Normally, this is done in the figure title of the graphics. Check the examples in the schematic illustration and table illustration. For details on the contents of the source citation, see the section documentation.

General guidelines for graphics � a review

The preceding sections repeat a number of common guidelines that need to be stated all in one place. These are important!

  • Use graphics whenever they would normally be necessary � don't wimp out because it seems like too much trouble! But at the same time, don't get hung up about creating perfect graphics (photocopies work just fine for our purposes as long as you cite your source). This course is a writing course, not a graphic-arts course.
  • Always discuss graphics in nearby text preceding the graphic. Don't just throw a graphic out there unexplained. Orient readers to the graphic; explain its basic meaning.
  • If a certain graphic is difficult to produce, discuss the problem with your instructor (you might be able to leave a blank with a descriptive note in the middle).
  • Make sure your graphics are appropriate to your audience, subject matter, and purpose � don't zap beginners with advanced, highly technical graphics they can't understand.
  • Intersperse graphics and text on the same page. Don't put graphics on pages by themselves; don't attach them to the end of documents.
  • Use figure titles for graphics (only a few exceptions to this rule).
  • Indicate the source of any graphic you have borrowed � this includes tables, illustrations, charts, and graphs. Whenever you borrow a graphic from some other source, document that fact in the figure title. This is explained in the section on documentation and is illustrated here in this chapter in the schematic illustration and table illustration.
  • Include identifying detail such as illustration labels, axis labels, keys, and so on. But don't hand-write them in � use the labels from the original photocopy or type them.
  • Make sure graphics fit within normal margins � if they don't, enlarge or reduce the copies. Leave at least 2 blank lines above and below graphics.
  • When you tape graphics in to your report, photocopy your entire report, not just the pages on which the tape-ins occur. Hand in the entire photocopied document, not the original and not a mixture of original and photocopied pages.
  • Don't manually add color or other detail on the pages of the final copy that you intend to submit � in other words, don't draw on the final copy. Any details like these should be added before photocopying. If you must have color, use color photocopying equipment.
  • Place graphics as near to the point in the text where they are relevant as is reasonable. However, if a graphic does not fit properly on one page, put it at the top of the next, and continue with regular text on the preceding page. Don't leave half a page blank just to keep a graphic near the text it is associated with.
  • Except for graphics that need no figure title, cross-reference all graphics from the appropriate text. In the cross-reference, give the figure number (figure title and page are optional), indicate the subject matter of the graphic, and provide explanatory information as necessary.
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