Lotus 1-2-3 is a spreadsheet for MS-DOS from Lotus Development Corporation. It can be programmed using macros and comes with a separate program to produce graphs and charts but this cannot be run at the same time as the spreadsheet. It has keyboard-driven pop-up menus as well as one-key commands, making it fast to operate. Lotus 1-2-3 supported EGA and later VGA graphics. Early versions used the filename extension "WK1".
Lotus 1-2-3 has been the subject of several user interface copyright court cases in the US.
1-2-3's successor, Lotus Symphony, had simultaneous update of spreadsheet, graph and word processor windows.