We are now starting to enter the heart of the paper. Like any project, your work is going to be partially built on existing components. In fact, it may be entirely built on existing components. Your contribution may be a new combination of the existing components that has not been tried before.
Now, some of these components will be necessary to understand your work. These components are what you should describe in your background section. That’s what we’re going to discuss today.
But what can you expect your audience to know? Which components need to be explained, and which can we assume that people know? The trick is to identify the components that you would need to tell someone else in your field, if that someone were to reimplement your approach. Try this exercise: pick a colleague, not in your lab, who you know personally. Then call him or her on the phone and explain how to implement your idea. Note whenever your colleague says “now, what is the XYZ again?” Those are the components you need to explain. You can even do this exercise in your head if you know your colleague well enough. You can anticipate the questions because you know what you know that he or she does not know. (Whew!)
Say you are developing a new treatment for an old skin disease. You propose that tiny doses of two different heart drugs will cure the disease. Your colleagues in dermatology might be aware of the heart drugs, but not how those drugs work. This is a good clue that you should explain it briefly — you want your audience to see your intuition about why your idea will work.
But watch out for the classic trap here. The trap is that you might start explaining your approach in the background. The temptation to do this is very strong: you have been working on the project for months or years. Your brain is in the details.
So, do NOT discuss ANYTHING about the approach yet. DO NOT DISCUSS THE APPROACH YET.
Instead, write down the 2-4 “must know” technologies. Then identify a few references that describe those technologies. Then start writing the background.
As usual, this is time for fancy talk. Use simple language. How about:
Section 3: Background
This section describes two supporting technologies for our work: ACME Portable Rockets (APR)  and Paintable Trick Walls (PTW) . These techniques were proposed elsewhere. We explain them here because we use them in our approach.
And now, one sub-section for each of those technologies. Remember, this ain’t Shakespeare:
Section 3.1: ACME Portable Rockets
ACME Portable Rockets are…
A typical application of APR is…
Section 3.2: Paintable Trick Walls
Paintable Trick Walls are…
A typical application of PTW is…
Expect each subsection to be 2-4 paragraphs. In each subsection, answer these questions:
- What are the inputs to the tool / technique / technology?
- What are the outputs of the technology?
- What is the primary mechanism of action of the technology?
- Who invented the technology (reference the original paper)?
- What are the typical application for the technology?
- What is the key advantage of the technology over competitors? (e.g., is it safer? faster? cheaper? what?)
Notice that the questions have NOTHING to do with your approach. You do NOT say anything about why the technologies are the best ones for your application, why you chose them, etc.
There are two reasons you want to avoid discussing your approach in the background section. First, it is what readers expect. When the section header says “Background”, your readers expect to hear about the background. Second, it makes the background much easier to write. You can write the background even if you have not finished the approach. In fact, you should write the background before the approach. It will help you better understand the tools you are using in your own work.
So, what are your supporting technologies?