What is peer-review? Watch this 3-minute video and find out.
How can you tell if a source is peer reviewed? Look it up in Ulrichsweb, the Global Serials Directory.
You'll be able to see if your publication is refereed (that's the same thing as peer reviewed), and it will display a little icon of a striped jersey (like a referee would wear) next to the title. You can click on the title for more information about the publication.