A Device-Independent bitmap (DIB) is a raster image file that is similar in structure to the standard Bitmap files(BMP). It contains a color table that describes the mapping of RGB colors to the pixel values. This enables DIB to represent images on any device. It can be opened with almost all applications that can open a standard BMP file on Windows as well as macOS.
Files with XLS extension represent Excel Binary File Format. Such files can be created by Microsoft Excel as well as other similar spreadsheet programs such as OpenOffice Calc or Apple Numbers. File saved by Excel are known as Workbook where each workbook can have one or more worksheets. Data is stored and displayed to users in table format in worksheet and can span numeric values, text data, formulas, external data connections, images and charts.