Corel Quattro Pro 1 (.wb1)
The WB1 file extension is associated with Corel Quattro Pro, a spreadsheet program developed by Borland and later sold by Alludo. It was used in version 5 of the software, which predates the more recent QPW format. Quattro Pro files, including WB1, are used to store spreadsheets containing data, formulas, and charts. Historically, Quattro Pro competed with Lotus 1-2-3 and Microsoft Excel, offering unique features like tabbed sheets and larger worksheet sizes.