A spreadsheet appears as a grid - each row has its own number and each column its own letter. This labelling of rows and columns is used to give each cell a cell address or reference, for example, C5 means column C, row 5.
It is also possible to refer to a range of cells collectively, ie E4:E12 includes E4, E12 and all of the cells in-between.
Cells can contain numbers, text or formulae.
A grocer uses a mobile shop to sell groceries to customers who live out of town. He uses a spreadsheet to keep a record of his daily sales:
There are a number of formulae in the above spreadsheet but they're hidden, only the results are displayed.
The formula in cells E2 to E8 works out the total value of sales for each item. It does this by multiplying the number sold by the individual price. For example, seven kilograms of apples were sold at 70p per kilogram, the sales total is calculated as £4.90 and is displayed in the cell E2. The formula in E2 is =C2*D2, ie 7 × £0.70.
Cell E12 contains a formula that calculates the total value of the sales column. The formulae used is =SUM(E2:E8). This formula includes cells E2, E8 and all of the cells in-between. You could write it =E2+E3+E4+E5+E6+E7+E8 which will give the same result but is overly complex and leaves more room for mistakes. Note, the =SUM function should only be used when adding a range of cells.