StockCharts Support April 16, 2009
Just like its name suggests, Market Summary is a single-page performance overview of the major elements of the market. Included in the summary are all of the major indices, sectors, and industries, as well as world markets, currencies, and even market breadth.
The colored bars are great for quickly analyzing performance. For your convenience, a variety of charts and views can instantly be created for any of the indices listed in the Summary.

There's also a Market Summary link on the Members page, in the Charts & Tools section.

The Market Summary is displayed on a single page. Within each section, the symbol and name of each index or stock is listed along with the latest closing price, change, percentage change, a colored bar representing the percentage change, and the date the statistics were taken from.

Three different charts can be created for each ticker symbol listed in the Summary. Click on the appropriate icon beside the symbol to open the chart in a new window:

Colored bars are shown for each ticker symbol, representing that symbol's percentage change. The size of the bar corresponds to the percentage amount; therefore, a very small percentage change will show as a very small bar.
For more information on the Market Summary check out this video.