Spreadsheets are very useful tools in public health because they are widely available, and can be used for collecting data, statistical analysis, constructing graphs and tables which can be exported into other applications or converted into image files. The basic function of Excel spreadsheets (for PCs) and Numbers (for Mac and iPad) is similar; they all consist of a matrix of rows (1, 2, 3, 4, etc.) and columns (A, B, C, ... Z, AA, AB, AB, etc.) which can be used to store text or numeric data and to perform a wide variety of mathematical and other functions that greatly facilitate analysis, organization, and reporting.

However, there are differences between Excel and Numbers in the user interface and the menus, and there are also differences among different versions of Excel. Nevertheless, the basic layout and functions within all of these are quite similar, and it is also noteworthy that Excel spreadsheets will open and run in Numbers, and Numbers spreadsheets can be "Saved as" Excel spreadsheets.

This tutorial will provide videos that illustrate the user interface for various versions of Excel and for Numbers '09. These will introduce users to whichever version of Excel or Numbers they have. The examples that we have developed to illustrate the application of spreadsheets in public health practice have been created in Excel, but the example spreadsheets can be downloaded and opened in whichever spreadsheet application you are using, and the examples are more or less generic and should be easily adapted to the spreadsheet you are using.