Hi Frank,

Its not clear to me if you are using Excel 2003 or 2007. Here is a post
that explains some of the advantages in the new 2007 file formats:

New file formats offer numerous advantages
Office 2007 introduces the XML-based Open XML file formats for Word, Excel,
and PowerPoint. These formats offer a number of significant advantages:

More compact size (the files are compressed)
Less chance of corrupted files (components are stored as separate entities,
so if one piece is damaged, the rest of the document is still viable)
Better integration of business information (users can more easily assemble
documents from various data sources, exchange data between Office and other
systems, and publish, locate, and reuse information)
Interoperability (information can be used by any application that can read
and write XML, not just Office apps)
Security (because of the transparent nature of the format, sensitive
information can be readily identified and removed; the format also allows you
to identify, isolate, and manage embedded code and macros)
Compatibility (the .doc, .xls, and .ppt binary formats are compatible with
Office 2007 apps, and users of Office 2000/XP/2003 can install the
Compatibility Pack so that they can open, edit, and save documents in the new
formats)
Open and royalty-free specification
Easier integration (developers have direct access to specific contents
within the file, like charts, comments, and document metadata without having
to parse entire documents)
This MSDN article covers various aspects of the new formats in some detail.

----------------
Excel 2007 stores files with the extension xlsx (amoung others) but these
are really zipped XML files.
If my memory serves me correctly Excel 2003 stores is files with the
extension xls but they are binary.

I'm sure you will get other useful feedback on this topic from others.
--
Cheers,
Shane Devenshire


"Frank Situmorang" wrote:

Hello,

To reduce the size, since it runs very slow, my subbordinate save it in
Excel Binay workbook, without my knowledge. Some of the formula does not not
work, so I asked her to change the xls extention in the formula into xlsb,
and it works.

My question is what other aspects that may impact our worksheets. Anyoen can
explain to me what is the difference in function this 2 formats .xls and xlsb

Thanks in advance
--
H. Frank Situmorang