Question marks are used to indicate that a statement's tone is asking something or inquiring.
Punctuation aids in telling where you are going with a statement to add meaning. "There is a concert tomorrow" sounds more exciting when you put "there is a concert tomorrow!". It makes you think it's worth going to see. A period tells you the sentence is over and you are through describing an issue. Otherwise you might be looking for more words to finish the sentence than there really is... ...see what I mean? Periods tell you when one sentence finishes, so you can start another. Commas tell you when a thought ends, but you are continuing on with the main idea. Quotation marks tell you it's a direct quote from someone.Then you know that this is exactly what the person said. You need to direct the reader in ways that words can't express on paper. In person, you would her the inflection or feeling as the person talks. He could also use body language to express excitement. On paper you have to use your imagination to color in the phrases. So, punctuation is a way to help communicate written thoughts and ideas from paper with more clarity. "Aren't you glad??!!!" Punctuations? You mean quotation marks? Well, I guess you can use them to quote material, show dialog, identify the title of a poem, etc., and you can use them to show how a certain word or phrase might be ironic. This can sometimes cause confusion. Take this headline for example: Ted Haggard says he is "completely pizzacrazy." Notice how the "completely pizzacrazy" could be (and probably should be) taken both as a quote and an ironic use of the phrase. If you just meant punctuation in general you should probably purchase a book on grammar, since that would be too much to explain in one of these little boxes. When you can use punctuation, according to the rules of English grammar, depends on which punctuation mark you want to use. The period, for instance, should be used at the end of a sentence, unless the sentence is a question. Then you would use a question mark. If you want to make a side comment (like this) in the middle of a sentence, use parentheses. Ellipses usually show omitted information... or a long pause in your thinking (informally). Here are a couple of links with more information; the first one is a writing center that has lessons and quizzes to help you learn, and the second is the wikipedia article with links to more kinds of punctuation: http://www.arts.uottawa.ca/writcent/hypergrammar/punct.html http://en.wikipedia.org/wiki/Punctuation