Understanding primary sources helps young people become critical thinkers. After learning about the many different types of primary sources, such as diaries, speeches, oral histories, video clips, photographs, newspaper articles, artifacts, and political cartoons, students will understand that they are able to draw their own conclusions about the content in a historical source. They will become aware of the biases and limitations of voices from and about the past. photographs feature multiple primary sources, while sidebars encourage readers to engage with the text.