A line chart is the simplest type of chart. As shown in the chart of General Motors in Figure 2, the single line represents the security's closing price on each day. A line chart's strength comes from its simplicity. It provides an uncluttered, easy to understand view of a security's price. Line charts are typically displayed using a security's closing prices.
Bar charts are the most popular type of security chart.
As illustrated in the bar chart in Figure 3, the top of each vertical bar represents the highest price that the security traded during the period, and the bottom of the bar represents the lowest price that it traded. If opening prices are available, they are signified by a tick on the left side of the bar. Most analysts only monitor the relative level of volume and as such, a volume scale is often not displayed. This means the bottom of each volume bar represents the value of zero. This is done by subtracting the lowest volume that occurred during the period displayed from all of the volume bars.