Why some words in the tag clouds are bigger than others?

Some might think why indeed some words in the tag-clouds are bigger than other words (Look top right corner). So I would like to explain that the size of the words change automatically and depends on how many entries each of them contain. For example, you can see that by the time of submission of this post a tag-word 'mile' is bigger in size than, let's say, a word 'trips'. Because, more entries were submitted to the website under the tag-word 'mile' that 'trips'. So, the more you submit stories and entries under the some specific tag-word, the bigger it gets in size.