Chapter 7: 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 can be 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 down 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. 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 Figure 7-1):
- 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 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.
- 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 Figure
7-1 and Figure 7-2.
Figure 7-1. 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.
Photographs
At least as the way things stand right now, 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 our technical writing course, consult with your
instructor. After all, this is a writing course, not a graphic arts
course--taped-in or photocopied photographs may be okay in this setting.
Tables
Tables of course are those rows and columns of numbers and words, mostly
numbers. They permit rapid access to and 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 these 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 (it's 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 are
row headings, which define or identify the contents of that row.
Things get tricky when rows or columns must be grouped or subdivided. Now,
you have to create row or column subheadings. This is illustrated in
Figure 7-2.
Figure 7-2. 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, in this technical writing
course, consider tables as figures (the same as illustrations and other
graphics), and number them within the same sequence.
As for specific formatting guidelines for tables, keep these in mind (most
of these guidelines are illustrated in Figure 7-3):
- 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 data.
- 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 Figure 7-1.
Figure 7-3. 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 in
Figure 7-4):
- 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--In bar charts, line graphs, and pie charts, you might be
using some special color, shading, or line style (solid or dashed). Be sure
to indicate what this means; translate them in a key (a box) in some unused
place in the chart or graph.
Figure 7-4. 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.
- 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).
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, or scan 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 Figure 7-1 and
Figure 7-2. For details on the contents of the source citation, see
Appendix B, page .
General guidelines for graphics--a review
The preceding sections repeat a number of general 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).
This course is a writing course, not a graphic-arts course.
- 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 all 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 Appendix B, page , and illustrated here in this chapter in
Figures 7-1 and 7-2.
- 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.
- Makes 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.
Return to the table of contents for the TCM1603 Course Guide
(the online textbook for Austin Community College's online
technical writing course).
This information is owned and maintained by David A. McMurrey. For
information on use, customization, or copies, e-mail
davidm@austin.cc.tx.us or call (512) 476-4949.