A chart will display a graphical representation of the data in your table/query.
It's not recommended that your chart tables with a large number of rows: the charting will be very slow and the results may not be meaningful. You may wish to summarize your data before charting it. The Summarize Data window helps you summarize your table, and this links into the Charting window.
You cannot chart a table/query if it contains no numeric columns.
The data points are spaced evenly on the horizontal axis. The exception to this is when Scaling is used - in this case the position of the data points on the horizontal axis is determined by the value of the label column. Scaling can only be used when the label column is numeric or date.
The above chart is an example of a Bar chart. AQT can create other types of charts, such as line, area, point and pie.
A set of data points for a column is called a Series. You can have multiple series - eg. you can can chart multiple columns.