◄Previous: 5.6 Reliability and usability

# 5.7 Structuring information

As you completed the table in Activity 20 you were probably skipping back and forth between the sections on 'WiFi' and 'Bluetooth' in Section 4. Did you notice that we used a rather different way of presenting our discussion in these sections? This was quite deliberate, because we want to investigate how these different approaches affect the way you extract information from written material.

You probably found it rather easier to search for and identify the information you needed about WiFi. The explanation was divided into different sections, and each had a clear heading. Because a few of the headings (e.g. 'WiFi data rates and operating range', and 'WiFi network structure' correspond quite closely to the row headings in Table 3, you would have been able to home in on what you wanted. Even where there wasn't such a direct link, the headings themselves provide a strong clue about the content of that section (e.g. 'WiFi stations').

The Bluetooth section is short, and this is why we decided not to use the same section headings that we used for WiFi. We felt this would have produced a very 'staccato' effect with some sections only a few words in length. The lack of section headings meant that there were no strong visual cues, and you may have found yourself having to scan the section two or three times to extract what you needed. Even so, I hope you found this to be a fairly easy task because of the way I had structured the information using paragraphs.

Click below to view a document for Activity 21.

View document

## Activity 21: self-assessment

Examine each of the six paragraphs in section 4.9 before Activity 19 (click on 'View document' above). Try to identify the main theme of each paragraph. (It will help if you number the paragraphs 1 to 6.)

### Answer

You will almost certainly have used different words to describe the main theme, but I hope we are in broad agreement over the topic of each paragraph.

1. Paragraph 1: The need for Bluetooth

2. Paragraph 2: Bluetooth standard – when developed and the parties involved

3. Paragraph 3: Transmission technology – frequency used and equipment needed

4. Paragraph 4: Piconets

5. Paragraph 5: Scatternets

6. Paragraph 6: Range and data rate

While you were working through Activity 21, you might have noticed that some paragraphs included a sentence that didn't seem to fit comfortably with the others. For example, the main topic of Paragraph 3 is the means of transmission and the equipment needed, but the final sentence is a bit at odds with this because it talks about how Bluetooth devices find each other. In my first draft I put this sentence at the beginning of Paragraph 4, but it didn't seem to fit very well there either because Paragraph 4 talks about the piconet structure and how communication is controlled within this network.

I could instead have isolated the sentence into a paragraph on its own, but single-sentence paragraphs work well only in particular situations – such as in pages of notes, in lists in the form of numbered or bulleted points, or in a very few situations when a single-sentence paragraph can be used to emphasise or draw attention to a particular point. So I chose instead to place this information within what I felt was the most closely related paragraph. After reflection Paragraph 3 won by a short head over Paragraph 4.

## Activity 22: exploratory

Paragraph 6 (of section 4.9) consists of just two sentences. Do they both fit comfortably together in the paragraph? Could they have been better placed elsewhere?

### Discussion

Here is my analysis.

The first sentence in Paragraph 6 is concerned with range, and what limits the range. The second sentence is about data rate and throughput. Nothing is discussed that links together these two properties, so they don't fit logically within the same paragraph. However, neither of them would fit comfortably in any of the foregoing paragraphs, and separating them would result in two single-sentence paragraphs. I felt that together they provided an acceptable ending to the Bluetooth section because they 'mopped up' the outstanding points I wanted to make.

On reflection, a better place for the whole of Paragraph 6 would have been after Paragraph 3, because Paragraph 3 ends with a comment about the relatively low power requirement of a Bluetooth transceiver, and Paragraph 6 starts by noting the effect of power output on range. This change of ordering would have provided a good link between the two ideas.

Decisions about headings, subheadings, grouping of points into paragraphs, and appropriate ordering of points are all concerned with the structure of a document. So are decisions about whether to use tables and numbered or bulleted lists, and where to position any figures used. Good technical explanations need to be carefully structured and clearly presented. A good structure will help the reader to follow the points the author is making and grasp the contents of a document more easily. You will need to think about this when you write your answers to assignments.

As an example of poor structure, look at the text below. It is intended to provide a short introduction to WiFi and Bluetooth technologies and a brief comparison of some of their characteristics.

WiFi is able to provide a data rate that is at least 10 times faster than Bluetooth, which is generally used for short-range communication between IT devices such as computers, printers, keyboards, PDAs etc. They both use the 2.4 GHz ISM radio frequency band. Bluetooth's transmission range is typically 10m. Because it uses a small low-power microchip rather than a NIC, Bluetooth is better suited for incorporation into small devices. It enables these devices to communicate without the need for cables linking them together. WiFi uses a network interface card (NIC) to transmit signals. Both WiFi and Bluetooth are defined by a set of standards produced by the IEEE. WiFi and Bluetooth are technologies that provide a means to transmit data wirelessly between devices. WiFi tends to be used in local area networks as an alternative to a wired network. WiFi's range is typically 30 m. ISM stands for 'industrial, scientific and medical'. IEEE stands for 'Institute of Electrical and Electronics Engineers'. PDA stands for 'personal digital assistant'.

If asked to rewrite this so that it is easier to follow, this is how I would approach the task. First I would look to see if I could group the points into a number of main topics. Here's what I found:

- points about differences in the two technologies and why these differences make them suitable for particular applications;

- points that are common to both WiFi and Bluetooth and provide a general introduction to the technologies;

- points about the network interfaces.

Next I would think about ordering, asking questions such as:

- Would the information be better divided into separate paragraphs?

- What would provide a good introduction?

- Do any of the points rely on information that should be given earlier?

## Activity 23: self-assessment

Using paragraphs, but no subheadings, rewrite the sample text so that it becomes easier for the reader to follow the points made. On the assumption that most of the information is new to the reader, make sure you cover all the information given, ordering and grouping it appropriately. (You don't have to stick to exactly the same wording and sentence structure as the original.)

### Answer

Although the sample was a fairly short piece of text, I felt that it would divide well into three separate paragraphs – one for each of the topics identified in the first set of bullet points before Activity 23.

Next I looked at ordering, deciding that the points that provided a general introduction to the technologies should come first. The explanation about the different interfaces provided some of the background to the different uses, so I put that next. I also made sure that I defined the meaning of each abbreviation as I used it (but if I used the abbreviation later in the document I didn't repeat the definition).

Here is my attempt:

WiFi and Bluetooth are technologies that provide a means of transmitting data wirelessly between devices. Both use the 2.4 GHz industrial, scientific and medical (ISM) radio frequency band and both are defined by a set of standards produced by the Institute of Electrical and Electronics Engineers (IEEE).

All devices need some kind of network interface to enable them to transmit and receive signals. WiFi uses a network interface card (NIC) but Bluetooth uses a small low-power microchip which is better suited for incorporation into small devices.

WiFi is able to transmit data up to 10 times faster than Bluetooth and has a greater range – typically 30 m compared to 10 m for Bluetooth. This makes it more suitable for use in local area networks where it can be used as an alternative to a wired network. Bluetooth, on the other hand, is generally used for short-range communication between IT devices such as computers, printers, keyboards and personal digital assistants (PDAs) where it eliminates the need for connecting cables.

◄Contents►Next: 6 Smart homes

OpenLearn - IT: device to device communication
Except for third party materials and otherwise, this content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence, full copyright detail can be found in the acknowledgements section. Please see full copyright statement for details.