Definition
Is a selfie data? Is a voice note?
Data comes in several types: numbers, text, images, audio and video. It can be structured, meaning arranged in fixed rows and columns like a table, or unstructured, meaning it has no fixed format, like photos, messages and recordings.
In simple words
A marks register is structured: every student has a row and every subject a column. A pile of WhatsApp messages is unstructured: each one is a different length and about something different. Most data in the world is unstructured, which is why AI that reads text and sees pictures matters so much.
Why it matters
Different types of data need different kinds of AI. Tables suit simple prediction models, photos need computer vision, and text needs language AI. Knowing the type of data is the first step in choosing how to use it.
How it works
| Type | Examples | Usually |
|---|---|---|
| Numbers | Marks, prices, temperatures | Structured |
| Text | Messages, reviews, books | Unstructured |
| Images | Photos, X-rays, satellite pictures | Unstructured |
| Audio | Voice notes, songs, bird calls | Unstructured |
| Video | Films, CCTV, sports clips | Unstructured |
Try it yourself
One phone, many kinds of data
Follow what a phone stores on a normal day.
Sort the data cards into types
Which type of data is each card?
A product review on a shopping site
Daily rainfall in millimetres
Your height in centimetres
A cricket match highlight
A selfie
A voice note to a friend
Structured or unstructured?
Does the data sit neatly in rows and columns?
Comments under a video
A spreadsheet of monthly expenses
A folder of holiday photos
A train timetable
Common mistakes
- Thinking only tables are data.
- Thinking unstructured means useless. It is the most common kind, and AI can learn from it.
- Forgetting that one item can hold several types, such as a video with sound and captions.
Check yourself
Summary
- Data types: numbers, text, images, audio and video.
- Structured data fits rows and columns; unstructured data does not.
- The type of data decides what kind of AI can learn from it.
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