Spreadsheets like Gnumeric treat information by separating the data into separate cells and considering the data in each cell to be separate elements. Each cell in the spreadsheet has both a value, which is what Gnumeric manipulates, and a representation, which is what is actually shown. Understanding this distinction is complicated and make take some time if you are new to spreadsheets. time. This distinction between value and representation is one of the reasons spreadsheets are so useful.
The cells of the spreadsheet are contained in the cell grid area. The cell grid area is the area with a white background and grey grid lines. The grid lines separate this area into separate cells. Each cell has a unique reference name which is the combination of the letters of the name of the column and the number of the row. For instance, the top, leftmost cell is the cell named "A1" and the cell two over to the right and four rows down is named "C4" because it is in the column labelled "C" and in the fourth row. Each of these cells can contain only one single datum.
The datum contained in any cell will have one of five types: a text string type, a number type, a formula type, a boolean type or an error type. These five types of data values can then have various display formats so that, for instance, a number value can be displayed as a number, a monetary amount, a date or a time. Text strings are sequences of characters and punctuation marks and could, for example, contain textual information such as people's names. Number values are simply numbers but may be input and displayed in various formats including decimal numbers, dates, times, and numbers in scientific notation. Formulas are instructions to Gnumeric to calculate a result. The power of spreadsheets comes from these formulas because the results of the calculation can depend on the contents of other cells. Boolean values are either TRUE or FALSE and can be used in logical statements. Error values are usually the result of mistakes or impossible calculations.
For more advanced information on the types of data usable in Gnumeric, see Section 5.2 ― The Types of Cell Elements.