I believe it was designed keeping in view the system limitations at the time
Excel was developed. It was probably not changed in later versions as it
probably required a major rewrite which MS finally took up for Excel 2007.
unfortunately most users did NOT like the new Excel despite many attractive
new features - people hate the RIBBON interface...
Following is copied from
http://spreadsheetpage.com/index.php/oddity/the_256_column_limitation/
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Every Excel worksheet is limited to 256 columns. Despite what must amount to
thousands of requests over the years, Microsoft refuses to increase the
number of columns in a worksheet. Beginners often discover this limitation
when they want to set up a spreadsheet that contains data for each day in a
year. If they store the data horizontally, they run out of column in
mid-September.
So we're stuck with 256. Why such a weird number? Why not 250? Or 365? The
number of rows and columns is a by-product of the binary number system. 256
is 2, raised to the eight power (2^8), which is the maximum value that can be
stored using eight bits. The number of rows in a worksheet is 65,536, which
is 2^16. Older versions of excel contained only 16,384 rows, which is 2^14
power.
The reason for the 256-column limitation is probably due to the fact that
Excel is so old, and it contains lots of code that would be broken if the
number of columns were increased.
Update: The 256-column limitation was lifted in Excel 2007. In addition,
that version has 1,048,576 rows in a worksheet.
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