Final answer:
Sparklines are miniature charts in a cell or cell range to illustrate trends or patterns, offering a simplified visual overview of data without occupying the space of a full chart.
Step-by-step explanation:
The miniature charts displayed in a cell or cell range to illustrate patterns or trends are known as sparklines. Sparklines are a feature in spreadsheets like Microsoft Excel that allow users to create small line graphs within a single cell. These tiny graphs are useful for visualizing data trends at a glance without the need for the full detail of a regular chart. They can show trends over time, similar to how a line graph can demonstrate changes in data points. Additionally, unlike other detailed graphs such as bar graphs, histograms, or stem-and-leaf plots, sparklines provide a simplified overview that saves space and can be embedded right next to the relevant data for quick reference.