Where in my essay should I cite?

Citation is possible all the way through. How you use citation depends on what you want to say! It can appear in your introduction, conclusion, and all the way through your essay! Be careful, however, not to clutter your paper with other people's ideas and forget your own! Especially in a research paper the temptation is to show more and more and more research - but you should remember that the research is supposed to add up to something - your cohesive answer to an essay question! So, don't forget YOU when using other sources. Also, be very careful not to fill your paper with quoted facts or obvious ideas. Only use citation when it is helpful - otherwise it just takes up space and distracts the reader from your ideas. Do not use citation to pad out an essay.