Smart Charts - Reading and Drawing Pictographs

A Pictograph is a way of representing data using pictures or symbols. It makes information easy to understand at a single glance by showing quantities visually through rows of icons.

The 'Key' or 'Scale' is a vital instruction usually placed at the bottom of the chart. It explains the value of a single symbol, for example, $1 \text{ symbol} = 10 \text{ units}$. Without the key, the pictograph cannot be interpreted correctly.

Data in a pictograph is organized into a table with rows and columns. One column contains the categories (like 'Types of Fruits' or 'Days of the Week'), and the rows show a horizontal line of pictures representing the count for that category.

To calculate the total value for any category, you must count the number of symbols in that row and multiply it by the value given in the key. The visual length of the row helps in comparing which category has more or less data.

Sometimes, a 'Half Symbol' is used to represent exactly half of the value assigned in the key. Visually, if a full circle represents $8$ people, a semi-circle (half-circle) would represent $4$ people.

When drawing a pictograph, it is important to choose a simple symbol that is easy to repeat. If you have large numbers like $50$ or $100$, you should choose a larger scale (like $1 \text{ symbol} = 10$) so that you don't have to draw too many icons.

Pictographs allow for quick visual comparison. By looking at the chart, the longest row of pictures represents the 'Mode' or the most frequent item, while the shortest row represents the least frequent item.