In 7 Zip when adding a folder to an archive there is the option to change the Word Size.
How does this word size affect compression, in particular the final size of the zip?
I noticed that changing the compression level increases the word size, however even on ultra it only selects a word size of 128 even though the largest option is over double that. Is there a reason why ultra doesn't select the largest? Is optimal compression size somewhere between the biggest and smallest word size?