According to JCU Academic Policies, "plagiarism is any use of another's ideas, words, or created product without crediting the source". This can include also charts, stats or drawings.
Even paraphrasing a part of a text without giving credit properly is considered plagiarism.
The MLA Handbook states that using another person's ideas, information, or expressions without acknowledging that person's work constitutes intellectual theft. Passing off another person's ideas, information, or expressions as your own to get a better grade or gain some other advantage constitutes fraud.
Plagiarism can be:
Re-using your own works (or parts of them), papers or statements multiple times without authorization can be self-plagiarism.
Be sure to ask your Instructor about the right to proceed with using your previous works and also about what citation style is preferred to use.
Check these online resources if you want to know more about Plagiarism and how to avoid it:
(video from Scribbr)
There are multiple ways to avoid plagiarism:
Properly giving credits to the original author: writing any piece of information that is not common knowledge; quoting written or spoken words and even paraphrasing requires the writer to give credits to the original author, either with an in-text citation, or by referencing the original source in the bibliography, following the Citation Style you are using.
Putting in quotation marks anything that is a direct quote (and is directly taken from a text) and write it as it is written.
Paraphrasing effectively to avoid plagiarism. As the 9th Edition of MLA Handbook states: "a paraphrase should convey the important information in a passage in your own words and sentence structure." Maintaining the same sentence structure and using synonyms in your paraphrase IS NOT sufficient to paraphrase.
Also, some terms cannot be paraphrased because they represent a definition or are a proper noun.
Here there is an example of an incorrect paraphrase and a correct one:
Original Quote:
Incorrect Paraphrase (only changes some words with synonyms and also maintains the same sentence structure, and also doesn't cite the source in the end)
Correct Paraphrase (restructures the sentences and uses a different wordings, maintaining the important facts and information)