Understanding Report Layout and Rendering
A report consists of three main areas: a page header, a page footer, and the body. The page header and footer repeat the same content at the top and bottom of each page of the report. You can place report items such as images, text boxes, and lines in headers and footers. The body of the report contains the report data. In addition to the report items that you can place in a header or footer, you can place data regions, which display the data from a dataset, anywhere in the report body.
The placement of report items in a report is completely freeform. With Reporting Services, you are not limited to "bands" of data in a report. You can place data regions with different sets of data side-by-side. Certain report items can also contain other report items. For data regions, this means that you can nest groups of data within other groups. For more information about data regions in Report Designer, see Understanding Data Regions. For more information about report items in Report Designer, see Working with Report Items.
When you run a report, the report server combines the layout from the report definition with the data from the data source, and renders the report in a specified format. The report server uses extensions to perform much of this work: a data processing extension is used to retrieve the data based on the type of data source, and a rendering extension is used to provide report output based on the selected format. Different extensions can change the way data is processed and the report is rendered. For more information, see Design Considerations for Report Rendering.
Pagination in a report is determined by the page size of the report and any page breaks placed on report items. Rendering extensions that support page size, such as image and PDF, format the data in the report to fit within each page. Rendering extensions that do not support page size render all data between page breaks on a single page. Some extensions that do not support page size may employ soft page breaks. The HTML rendering extension does this. The position of soft page breaks are determined by the size of the page, but are not as exact as page breaks placed by rendering extensions that support page size. All rendering extensions that support page breaks on items will start a new page after each page break in the report. For more information about working with page size and page breaks in Report Designer, see Controlling Report Pagination.