Why do tab delimited files take up less space than commas?

Question

I noticed that the same data stored in a separate file with a tab takes up less space than when this data is stored in a file separated by a comma.

My first thought was that tabs take up more space than commas, but all I can find is that they take up the same amount of disk space in UTF / Ascii.

Answer 1

The CSV version probably has quotes around the data fields (just in case they contain commas).