According to Source It: A Guide to Documenting your Work, published by the Peel District school board, Plagiarism is the act of presenting someone else's words or ideas as your own by failing to give them credit.  Academic dishonesty is a serious offence and often results in a mark of zero.  

While some students do this intentionally, many others do so because they are disorganized.  The best way to avoid plagiarism is to be organized and to take good notes.  Always record the source information first - before you use any ideas in your research.   If you copy anything, a good strategy is to highlight it so that you immediately know the information is not yours!
                                                                                                           

When do I have to cite my source?

The Peel District School Board outlines when you have to cite your source:

When you use ideas, pictures, maps or quotations from other sources, you must give those sources credit.  Even if you paraphrase or summarize the original, you still must give credit.  All items must be cited in the text of your essay with embedded citations (also known as in-text citations), endnotes, or footnotes.  Also, each item must be described in more detail at the end of the document in the "Works Cited",  "References" or, "Bibliography" page.  The specifics for citing will vary depending on the style that your instructor requests.  Failure to give credit to the original author is considered plagiarism, which is a serious academic offence.  Most schools will assign a mark of zero to a submission that is plagiarized. This may result in the loss of credit.  

What must be Cited:

• Quotations
• Images, art, maps, photographs, charts
• Paraphrased information
• Summarized information
• Cartoons
• Advertisements
• Audio Visual Materials (music, radio, DVDs, MP3 files, broadcasts, etc.)
• Statistics

What is not Cited:

• Your own ideas or analysis
• Primary Research (surveys that you conducted)
• Commonly known information (i.e. the earth is round, we breathe oxygen, who the Canadian prime minister is, etc.)

So, what style of citation do I use?

Ask your teacher what type of citation he or she prefers.  Generally, English and History will use MLA, while science, social science and the arts will use APA citation format.

The following are examples used by the University of British Columbia to guide student writing and avoid plagiarism:
EXAMPLES
This is an example of plagiarism (in the form of paraphrasing). The boldface type indicates the common words that are used in the original, the plagiarized version, and the acceptable version.
ORIGINAL TEXT:
From Sharon Venne's journal article "Understanding Treaty 6: An Indigenous Perspective", in Aboriginal and Treaty Rights in Canada: Essays on Law, Equity, and Respect for Difference, Ed. Michael Ash, Vancouver: UBC Press, 1997.
For an understanding of the relationship between the Treaty Peoples and the Crown of Great Britain and later Canada, one must consider a number of factors beyond the treaty's written text. First, the written text expresses only the government of Canada's view of the treaty relationship: it does not embody the negotiated agreement. Even the written versions of treaties have been subject to considerable interpretation, and they may be scantily supported by reports or other information about the treaty negotiations.

PLAGIARIZED VERSION:
In order to understand the relationship between First Nations Peoples and the government of Canada, one must look beyond the written text of the treaties. First, the written text expresses only the government of Canada's view of the treaty relationship: it does not embody the negotiated agreement. Even the written versions of treaties have been subject to considerable interpretation, and they may be scantily supported by reports or other information about the treaty negotiations.

ACCEPTABLE VERSION:
Sharon Venne believes that written treaties are insufficient in developing an understanding of the issues between the First Nations Peoples and the government:

The written text expresses only the government of Canada's view of the treaty relationship: it does not embody the negotiated agreement. Even the written versions of treaties have been subject to considerable interpretation, and they may be scantily supported by reports or other information about the treaty negotiations. (173)

This viewpoint, however, has often made researchers disregard the treaties, a dangerous tactic when discussing the issues mentioned above.

The acceptable version credits the original author for the initial idea, and indicates, by indentation, the words that are taken directly from the original text. Information regarding the original text is offered so that readers can find the quotation for themselves. The quotation is followed by the student's evaluative comment and the quoted text is integrated into the essay in an original line of thought.

To Avoid Plagiarism...properly source your work! See below for details on how to use citations...

Using APA Format

Using MLA Format

CITATION MACHINE - THE LANDMARK PROJECT

Citation Machine is an interactive Web tool designed to assist teachers and students in producing reference citations for crediting information from other people. You merely...

1. Click the type of resource you wish to cite,
2. Complete the Web form that appears with information from your resource, and
3. Click Make Citations to generate standard MLA & APA citations.

http://www.landmark-project.com/

There are three basic ways to cite a reference - embedded citations, footnotes or endnotes. Use the following guidelines...

EMBEDDED CITATIONS

Recent publications favour the use of embedded notes:

Example:

Lincoln's death did not draw any "nobler expression" of national grief than Whitman's poem "O Captain! My Captain!" (Rossetti 143)

Try to make a smooth transition between the text and the quotation, by introducing the quotation appropriately, for example by incorporating the author's name into your text.

e.g. As Flora Davis has noted, "..."(40)

When a quotation is greater than 2 lines or 2 sentences, indent 10 spaces (right and left) and use single spacing. Do not use quotation marks.

When omitting a full sentence or more from a quotation, use a period and 3 ellipses (. . .)with spaces in between.

e.g. According to Wade, the horse Clever Hans "could apparently count by tapping out numbers with his hoof. . . Clever Hans owes celebrity to his master's innocence"(1349).

FOOTNOTES

Footnotes should be numbered consecutively throughout the paper in Arabic numerals. Do not use asterisks or other symbols. In your text, place footnote numbers slightly above the line, following the quotation, thus: "It has been observed that imagery is a topic which belongs both to psychology and to literary I study."3
Separate footnotes from the body of the text by a solid line (if keyed 20 spaces long).

A footnote must appear at the foot of the same page on which it has been cited.
Indent footnotes 1" if handwritten, 5 spaces if keyed.
When using footnotes or endnotes always single space them and leave a space between each.
n.p. means "no place" or "no publisher" or both. n.d. means "no date".

ENDNOTES

Endnotes The notes should appear on a separate page just before the bibliography; numbered and in the order they appear in the text of your essay.

See examples of MLA and APA styles