*Workbook vs. Worksheet*– when you open Excel, a new file is created called Book 1 (until you name it differently). It is called “Book” because it is a Workbook that is initially made up of three Worksheets. Think of a three ring binder with three sheets of paper in it. As with a binder, you can add sheets to your Workbook (**Insert > Worksheet**), delete them, and re-arrange them. Double click on the Worksheet title to rename it.*Row*– rows travel horizontally and are numbered.*Column*– columns travel vertically and are assigned letters.*Cell*– cells are the basic rectangular building blocks of a spreadsheet. They are assigned an address, generally referred to as a*cell reference*, according to their column and row (e.g. the cell in column B at row 3 is referenced as cell B3).*Formula*– a mathematical formula used to calculate a result based on data from one or more other cells. Often they consist of some combination of the standard mathematical operators ( +, -, *, /) (e.g.:`=(A1+A5)/B13`

). But they may also include*functions*(see below). When you type a formula into a cell, that cell will generally display the result obtained by the formula, rather than the formula itself.*Functions*– pre-written formulae that perform common (and not so common) calculations, such as summation and averaging. You can combine many functions and operators in a single formula to obtain more complex results (e.g.:`=SUM(A1:A13)`

).