Excel is the full-featured spreadsheet program that’s part of Microsoft Office 2013. You can use Excel to perform calculations, create charts, and analyze data.
An Excel file is called a workbook, identified with the extension .xls. Each workbook contains one or more worksheets, each identified with a unique tab at the bottom of the screen.
A worksheet consists of a series of columns and rows; up to 256 columns and 16,384 rows, if you need them. At the intersection of a column and row is a cell, where you enter data and perform calculations.