A spreadsheet is a computer application with tools that increase the user's productivity in capturing, analyzing, and sharing tabular data sets. It displays multiple cells usually in a two-dimensional matrix or grid consisting of rows and columns (in other words, a table, hence "tabular"). Each cell contains alphanumeric text, numeric values, or formulas. A formula defines how the content of that cell is to be calculated from the contents of any other cell (or combination of cells) each time any cell is updated. A pseudo third dimension to the matrix is sometimes applied as another layer, or layers/sheets, of two-dimensional data.
Spreadsheets developed as computerized simulations of paper accounting worksheets. They boost productivity because of their ability to re-calculate the entire sheet automatically after a change to a single cell is made (which was a manual process in the days of paper ledgers). Spreadsheets have now replaced paper-based systems throughout the business world, with any exceptions being rare, because of the much greater productivity that they make possible, and thus the competitive disadvantage of spreadsheet illiteracy. Although they were first developed for accounting or bookkeeping tasks, they now are used extensively in any context where tabular lists are built, sorted, and shared.