What is the difference between XML and XLS?

Related questions

1. How do I open an XLS file in Excel Online?
2. What is XLS file format?
3. Is Microsoft Office Online Free?
4. How do I open XLS files in Excel 2013?
5. Is there a free program like Excel?
6. What is XLS format?

Tags

1. #extensible
2. #excel
3. #affected
4. #applications
5. #based
6. #being
7. #markup
8. #stands
9. #opened
10. #language
11. #while
12. #change
13. #editors
14. #which
15. #format
16. #replaced
17. #binary
18. #cannot
19. #actually