Let us see how we use an asterisk. The generally accepted rule for using an asterisk is to make sure it refers to something at the bottom of the same page. Have you noticed how some ads have an asterisk next to some offer, and then you can’t find what it means! It goes something like this: Buy XXXYYY, 20% off*! Then nothing else on the page to indicate what the asterisk means. What do we make of it? When you use the asterisk as a footnote symbol, you say that you are planning to comment on something at the bottom of the page. That is a promise, so you should keep it.
So, this is how you use an asterisk – you place it after something to show that you want to comment on it, or say something more about it. Then you write about that word at the bottom of the page. Historically, asterisks were also used to show that something was omitted or that some time had elapsed since the comment was made. That use has been largely taken over by the ellipsis (the omission from speech or writing of a word or words, marked by three dots …).
Today, the asterisk is used for adding information, especially when you need to avoid letters or numbers.
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