This applies to anything you see or read, but don't just accept what your information sources say without thinking critically about them.  Critical thinking is "thinking about thinking" - deciding whether is something is true by thinking about the evidence for and against it, and is an important part of academic writing.  When you form your argument, you do so on the basis of evidence.  That evidence will come from you thinking critically about the sources you have found.  Suppose you come across an article that says, "Butter is good for you!" "You should eat a pound of butter every day!"  and then you see that the article was written by someone who works for the Butter Manufacturers Association, wouldn't you think this was a little suspicious?

Critical thinking might sound complicated and difficult, but if you stop to think about it, you use - or should be using - the same skills in real life. When you make a decision, you base it on evidence.  When you go to the cinema, why do you choose to watch a particular film?  Perhaps you like the actors, the film got very good reviews, or maybe you like other films of the same type.  Why did you choose to do this particular course at this particular college? You don't just make decisions at random,;you think about them and weigh up the evidence before choosing.

So, you're doing the same thing here, but for information sources instead of choosing a film to watch.  It's a little removed from the real world (and less fun too), which is why you might think it's difficult, but the principles are the same. 

Critical thinking involves:

Here are some questions you can ask about the sources of information that you find: