Any collection of facts, numbers, measures, observations or other descriptions of things that convey information about those things is called data.
To organise data systematically, we can use tally marks. A tally mark $|$ represents one occurrence. When the count reaches $5$, a diagonal line is drawn through the previous four marks to represent a group of five: $\cancel{||||}$.
The number of times a particular value or preference occurs is called its frequency.
A pictograph represents data through pictures or symbols of objects. It helps in understanding and interpreting data at a quick glance.
A scale or key is essential to define what each symbol represents. For example:
Preparing a pictograph can be challenging when the data is large or when frequencies are not exact multiples of the scale.
A bar graph (or column graph) is a visual representation of data using bars of uniform width, drawn horizontally or vertically with equal spacing between them.
To draw a bar graph, follow these steps:
Visual presentations should be appealing, easy to understand, and fit the intended space. Choosing the correct scale and orientation is crucial.
Infographics (information graphics) are data visualisations beautified with extensive artistic and visual imagery to attract attention and communicate information quickly.
Caution: While infographics are visually appealing, they can sometimes be misleading if the proportions (such as width and height) are not maintained accurately.