Pie charts are widely used data visualization tools that represent whole data divided into multiple parts or slices, each representing a subcategory of the complete data. They can be used to answer various questions such as identifying the least traded stock volume, highest traded stock, and percentage of accrued votes in an election. The tutorial aims to teach users how to create beautiful and insightful pie charts using Grafana, a web application that utilizes PostgreSQL and TimescaleDB for analytics and interactive visualization. It will cover creating pie and donut charts with pre-aggregated data using time_bucket and show transaction volume in the same panel, providing real-world examples of pie chart creation in Grafana.