Graphics

A key feature of technical texts, particularly those aimed at consumers and those which have an instructional function, is the use of graphics and illustrations. Such graphics may include diagrams, graphs, schematics, photographs, screenshots or any other visual representation or information. This is particularly true of documentation for software products where providing a picture of what users are supposed to see on a screen is infinitely more effective than any amount of verbal descriptions.

Using screenshots to illustrate a software interface does mean, however, that a document which contains these references is inexorably linked with an entity which is outside the document

In order for such a text to be coherent, i.e. to make sense within its situation (Baker 1992:239), it must accurately reproduce the text contained in the software interface. As a result, any changes to the software will necessitate changes to the document. It also means any textual references to the software which are contained within the text must be phrased consistently and accurately. From this point of view, the text effectively becomes something of a multimedia, and possibly even a multimodal, text.

Other graphical references, which can be found in all types of technical documentation, relate to diagrams in which various components or items are labelled. Again, the aim is to convey information to readers clearly, quickly and effectively.

Figure 5: Technical diagram with labels

Formulae, equations and scientific notation

Second only to specialized terminology in its ability to make scientific and techni­cal texts look incredibly intimidating and complex to an unsuspecting translator is the use of formulae, equations and scientific notation. These are fundamental components of how scientists and technicians communicate and they perform a number of essential functions in texts, the most important of which is that they allow abstract concepts and ideas to be expressed clearly and concisely.

One of the most basic methods for expressing complex scientific and techni­cal information is scientific notation, which is also known as standard form or as exponential notation. This makes it easier to present figures which are too large or small to be conveniently written in standard decimal notation. The examples shown in Table 1 show how scientific notation works:

Ordinary decimal notation	Scientific notation
900	9xl02
8,000	8xl03
4,370,000,000	4.37xl09
-0.0000000031	-3.1X10-9

Table 1: Expressing decimal numbers in scientific notation

Unless we are dealing with purely mathematical texts, numbers, whether in ordin­ary decimal or scientific notation, will rarely appear in isolation. In the majority of cases, numbers are used to quantify something and unless we know what it is we are quantifying, the numbers are quite useless. For this reason, texts will feature a variety of units of measure. Units of measure are definite amounts of some physical quantity, such as length or weight. They are agreed upon, adopted and used by convention, and are represented by a unique symbol. In most cases, units of measure are governed by the International System of Units, known as SI for short. The SI sets out seven base units of measure:

• length - metre (Symbol: m)

• mass - kilogram (Symbol: kg)

• time - Second (Symbol: s)

• electric current - Ampere (Symbol: A)

• thermodynamic temperature - Kelvin (Symbol: K)

• amount of substance - Mole (Symbol: mol)

• luminous intensity - Candela (Symbol: cd)

Each of these units can be modified by means of prefixes such as micro-, milli-, nano-, pico- etc. Interestingly, the SI prefixes can also be used independently of SI units of measure, for example with Imperial measures, with the result that you can conceivably see things like kilofoot (kft) or microinch {pin). In addition to the base units, there are various other units which are typically named after scientists who discovered them, such as farad (F) which is a unit of capacitance and is named after Michael Faraday, volt (v) the unit of electric potential dif­ference which is named after Alessandro Volta or watt (W), the unit of power which is named after James Watt. All of these standardized units of measure are governed by the SI and are a staple of scientific and technical communication. Appendix 1 contains a list of other eponymous units of measure.

While metric measurements are rapidly becoming the norm internationally, you should not be surprised to see Imperial units of measurement sometimes being used in certain languages, particularly English. This is especially true in certain types of technical text such as workshop manuals, specifications or parts catalogues where inches, feet, pounds and ounces are still sometimes used.

A formula is a concise way of expressing information such as chemical reac­tions or mathematical operations in a symbolic manner. They can also be used to express general relationships between quantities or variables. The advantage of using formulae is that they are invariably more compact than any alternative verbal descriptions; they are accurate because there is no room for interpreta­tion of words. Equally important is the fact that formulae are widely regarded as virtually universally intelligible. Indeed, mathematics was once described by Kasner and Newman as "a universal language, valid, useful, intelligible every­where in place and time" (1940:358).

While scholars such as Montgomery might argue against this view of math­ematics on the grounds that "even the most densely mathematical research takes place in a linguistic context" (2002:254) it is hard to imagine that this context would prevent a mathematician working in one language from comprehend­ing equations written by a mathematician from halfway around the world. The reason for this is that equations are invariably accompanied by a list or brief paragraph which identifies and defines each symbol in the equation and assigns a value to it. A phrase which commonly appears after an equation to introduce these definitions is "Where X equals V". As a result, providing the symbols have been clearly identified and explained, a mathematician should have no problem understanding any equation.