"Introduction" may be a noun, but it comes from the verb to introduce. It can refer to different things:
- The action of introducing someone to another someone, or something
- A specific written or prepared piece of text or speech with the purpose of providing introductory information.
Let's say for example that you had prepared an entry-level presentation designed for people with little or no knowledge of the subject matter at all. You could describe the entire presentation as:
An introduction to [subject]
As a second example, let's say that your prepared presentation is broken down into different sections, the first section of which is designed to welcome your audience and brief them on some essential matters before the rest of the presentation. This first section may be called the introduction, and you may say of that section:
The introduction is about [subjects covered in this section]
The difference in the two is that the first is using the word "introduction" to describe the action of introducing people to a subject, while the second is using the word "introduction" as the name of something which is about a subject or subjects.
In your personal example, I would say the correct rendition is:
This section presents (or "includes", or simply "is") a short introduction to [something]