<Tr> <Td> Spreadsheet </Td> <Td>. xls </Td> <Td> Main spreadsheet format which holds data in worksheets, charts, and macros </Td> </Tr> <Tr> <Td> Add - in (VBA) </Td> <Td>. xla </Td> <Td> Adds custom functionality; written in VBA </Td> </Tr> <Tr> <Td> Toolbar </Td> <Td>. xlb </Td> <Td> The file extension where Microsoft Excel custom toolbar settings are stored . </Td> </Tr> <Tr> <Td> Chart </Td> <Td>. xlc </Td> <Td> A chart created with data from a Microsoft Excel spreadsheet that only saves the chart . To save the chart and spreadsheet save as . XLS . XLC is not supported in Excel 2007 or in any newer versions of Excel . </Td> </Tr>

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