 This system results in letters like 's' appearing much more frequently, such as when counting letters from lists of the most used English words on the Internet.A final variant is to count letters based on their frequency of use in actual texts, resulting in certain letter combinations like 'th' becoming more common due to the frequent use of common words like "the", "then", "both", etc.Absolute usage frequency measures like this are used when creating keyboard layouts or letter frequencies in old fashioned printing presses.