Types of Data

Data comes from many sources, and its format depends entirely on where it originates. An image is a grid of pixels, a video is a sequence of frames, a fee slip mixes numbers and text, and a chat message can contain text, emojis, and media. Because of this variety, data is classified into two broad categories based on its format: structured and unstructured.

(A) Structured Data

Data that is organised and can be recorded in a well-defined format is called structured data. It is typically stored in a computer in a tabular form — that is, in rows and columns.

• Each column represents a particular parameter, also called an attribute, characteristic, or variable.
• Each row represents a single observation — the data for one entity across all attributes.

For example, consider the inventory of kitchen items in a shop. The data can be arranged in a table where columns are Model Number, Product Name, Unit Price, Discount (%), and Items in Inventory. Each row gives the details for one product.

The textbook provides several other examples of structured data, each with its own set of attributes: