Capitalization:
On a computer keyboard capitalization helps to indicate tone of voice. It is impolite to type all in capital letters, for example, because this means that you are shouting, something you would not do in a face-to-face conversation. It is advisable to capitalize words only when you want to highlight an important point. The standard rules of capitalization (proper nouns, the first word in a sentence, etc.) apply to electronic correspondence as they do for any other correspondence.
In the same way that capitalization indicates something that you want to have stand out, asterisks around a word highlight or give inflection, or emphasis to that word. For example, you *can* type in all capital letters, but it would be considered *extremely* rude! Alternately, you may show emphasis by using the underscore key _ before _ and _after_ any words to be emphasized, as if they were underlined.
(I was waiting for you to come back on and post in all caps. Had this ready for you...LOL)
