The word "asterisk" is a derivative of the Latin "aster," meaning "star," and hence, the asterisk is a little star. When speaking, many people make the error of omitting the second s, or replacing it with an x, ending the word with a "rik" or a "rix" rather than "risk." Such pronunciation perhaps stems from the transposition of the last two letters, s and k. The correct pronunciation requires a little preciseness, which might make some feel that it comes across as affected or pretentious speech when it is simply correct.
Use an asterisk (*) in a body of text to indicate a footnote. This placement specifies where an author wants to provide extra information on a particular subject by way of additional information or clarification.
Use an asterisk in English grammar in the place of omitted material in a report or paper. For example, you may refer to a body of text that's too large to include in the paper. So at the correct reference point, place an asterisk and then at the bottom of the page provide a fuller explanation of the source.
Use an asterisk to combine points or denote numerical values where there may be more than one point of clarification. For the first point, you can put an asterisk with a footnote preceded by one asterisk. For the next point, you can put two asterisks with the corresponding footnote preceded by two asterisks, and three and so on.
Place an asterisk when emphasizing a particular passage or word in a text that's being read or displayed. For instance, if an author wants to highlight a particular position, he can use an asterisk with a footnote or along with another notation, N.B., which tells the reader to take note of what he's reading.