If your assignment requires an overview of a topic from different political or social perspectives, then it will be necessary to identify and recognize the bias represented in specific magazines, newspapers, and websites/blogs. Here are two lists to help you:
We are surrounded by information every waking moment --on the Web, in books and articles, on TV, radio, billboards, and even food labels. But not all kinds of information are appropriate for all kinds of needs.
Whether you need information to solve a problem or for an assignment, it's important to critically analyze or evaluate the information that you find. Clearly understanding the kind of information that you have is an essential step towards making an educated decision about whether it is a good match for your problem or assignment.
This video tutorial from Western University explains the C.R.A.A.P. test.
These guidelines are general enough so that you can use them to evaluate all kinds of information regardless of format or where you find it.