For this assignment, you need to visit the National Archives Experience. Historians typically use two types of materials, secondary source, and primary source documents. Secondary sources are typically books and articles written on a particular historical event, well after the fact. Primary source documents are usually generated by first-hand participants. Good historians rely heavily on original materials created at the time of the event. For this reason, historians spend a good deal of time at the archives. There are many types of archives, but by far, the largest in the United States, is the National Archives in Washington, D.C. The National Archives contains more than 10 billion documents, and they have collected over 1,200 of those in the National Archives Experience. After you have opened the above link, click on continue in the bottom right corner. This will take you to the Experience site. Here, you can select a topic, and collect documents relevant to that aspect of history. Battle of Bull Run PowerPoint Presentation: To complete the power point you will need to collect your images from the internet. Be sure to cite all images collected elsewhere a. Must include a minimum of five slides. b. Presentation must include a narrative that explains the historical significance.