(XYSeries: The most commonly used data frame, mainly including a series of double type (x, y) point pairs and a title (title). XYValueSeries: includes a series of (x, y, value) pairs and a title (title). XYMultipleSeriesDataset: includes a series of XYSeries, which is the final data frame TimeSeries: similar to XYSeries, x becomes Date type and can be converted into XYSeries. CategorySeries: Similar to XYSeries, x becomes string type and can be converted to XYSeries.)