Many students begin to read a selection without identifying or thinking about the topic beforehand.
This means that they are probably not aware that what they already know is an essential factor in understanding the material to be read. The background or prior knowledge that students bring to the reading of a selection may be the most important factor affecting how well they comprehend. It is nearly impossible for students to understand material that they have been given to read if they have little or no personal knowledge of the topic. Comprehension occurs when the information that is being read is connected with that which is already known. If readers do not make the connection, then there is limited comprehension.