1. In the browser view of a workbook, you can navigate through the workbook, sort, filter, expand and collapse PivotTables, and even recalculate the workbook.
2. The data you are viewing is live. You can refresh a PivotTable, or refresh the whole workbook.
3. Click Edit in Browser to edit the workbook in the browser; click Open in Excel to work on it in the Excel desktop application.
4. When you edit the workbook in your browser, you can enter data and formulas, create tables and charts, and do some formatting. To enter formulas, type equal-sign (=), and then the formula or function. For help with Excel functions, see the Excel functions (by category).
5. Excel Web App has the look and feel of Excel.
Click the File tab to save a copy of the workbook or download a snapshot that contains just values and formatting, no live data.
The Home tab has commands for formatting text and cells, adding rows and columns, and recalculating data.
Use the Insert tab to add charts, tables and hyperlinks to your worksheets.
Excel Web App saves your work automatically. Use Undo to get rid of changes you don't want to keep.
6. If other people are working on the workbook, you can see who they are by clicking in the bottom right corner of the browser window.