Why was NATO formed?

Why was NATO formed? Why did Canada become a part of NATO? How was NATO related to the cold war?" 1st...PRELIMINARY REPORT...I need a preliminary report. A paragraph of about 200 words givining a description of my paper. What will be the central focus of the paper? What it will attempt to show or prove? THEN write a paragraph about 200 words describing what you have done so on the paper. Be specific. This should be a progress report on the Essay. Describe how you identifies and located the sources you are using.(Try and use a variety of sources. Include some general and some sources more specifically and directly related to to your topic. Essay between 2000 to 2500 words.