Many people consider plagiarism as copying another’s work, or borrowing someone else’s original ideas. However, terms like “copying” and “borrowing” can disguise the seriousness of the offense: According to the Merriam-Webster Online Dictionary, to “plagiarize” means
1) To steal and pass off (the ideas or words of another) as one's own.
2) To use (another's production) without crediting the source.
3) To commit literary theft.
4) To present as new and original an idea or product derived from an existing source. In other words, plagiarism is an act of fraud. It involves both stealing someone else’s work and lying about it afterward.

All of the following are considered plagiarism:

• Turning in someone else’s work as your own.
• Copying words or ideas from someone else without giving credit.
• Failing to put a quotation in quotation marks.
• Giving incorrect information about the source of a quotation.
• Changing words but copying the sentence structure of a source without giving credit.
• Copying so many words or ideas from a source that it makes up the majority of your work, whether you give credit or not (see our section on “fair use” rules).

Attention! Changing the words of an original source is not sufficient to prevent plagiarism. If you have retained the essential idea of an original source, and have not cited it, then no matter how drastically you may have altered its context or presentation, you have still plagiarized. Most cases of plagiarism can be avoided, however, by citing sources. Simply acknowledging that certain material has been borrowed, and providing your audience with the information necessary to find that source, is usually enough to prevent plagiarism. Simply, plagiarism is the use of another's original words, methods or ideas as though they were your own. Any time you borrow from an original source and do not give proper credit, you have committed plagiarism and violated copyright laws.

Types of plagiarism

1. Plagiarism of ideas

Presenting an idea (e.g., an explanation, a theory, a conclusion, a hypothesis, a metaphor) in whole or in part, or with some modifications without giving credit to its originator. Ethical writing demands that ideas, data, and conclusions that are borrowed from others and used as the foundation of one’s own contributions to the literature, must be properly acknowledged. The specific manner in which we make such acknowledgement varies from discipline to discipline. However, source attribution typically takes the form of either a footnote or a reference citation.

2. Plagiarism of text

Copying a portion of text from another source without giving credit to its author and without enclosing the borrowed text in quotation marks. When it comes to using others’ word-for-word (verbatim) text in our writing the universally accepted rule is to enclose that information in quotations and to indicate the specific source of that text. When quoting text from other sources, you must provide a reference citation and the page number indicating where the text comes from. Although the use of direct quotes is uncommon in the biomedical literature, there may be occasions when it is warranted.

3. Inappropriate paraphrasing

Taking portions of text from one or more sources, crediting the author/s, but only changing one or two words or simply rearranging the order, voice (i.e., active vs. passive) and/or tense of the sentences. Inappropriate paraphrasing is perhaps the most common form of plagiarism and, at the same time, the most controversial as the criteria for what constitutes proper paraphrasing are not universal. However, to make sure that one is not committing an act of plagiarism it is better to substantially modify the original text and clearly acknowledge its authors.

4. Self plagiarism

Self-plagiarism occurs when authors reuse their own previously written work or data in a ‘new’ written product without letting the reader know that this material has appeared elsewhere. This is also known as double (duplicate, redundant, dual) publication.

Why do authors plagiarize?

A. Intentional Plagiarism

1. Academic promotion

Academic doctors are required to publish in order to guarantee their academic promotion. Furthermore, they are sometimes under pressure from their work and peers to publish. They often see research and academic duties as a step in the ladder to success, and not an active process valuable in itself. Because of this, some doctors tend to focus on the end results of their research, rather than the skills they learn in doing it.

2. “Everyone else is doing it”

Doctors often justify plagiarism by pointing out that since their peers plagiarize, they must do the same to keep up. They feel faced with a choice: to put several hours of work and risk an unpredictable poor outcome, or to do what their peers do and copy something good from the internet for an easy and successful outcome.

3. Poor Planning

Doctors even those who acquire academic posts are not always the best judges of how much time their writing assignments can take. They may also not be totally aware of the extent of work involved in a research paper, or may simply be overwhelmed by their clinical duties leaving them with no time for original work of their own.

B. Unintentional Plagiarism

1. Citation Confusion

Perhaps the most common reason for inadvertent plagiarism is simply an ignorance of the proper forms of citation.

2. Inappropriate Paraphrasing

Many authors have trouble knowing when they are plagiarizing as they consider themselves to have properly paraphrased the original text when they actually have not.

3. Not finding the source

Authors are sometimes not careful about writing down the bibliographic information (references) of their sources, leaving them unable to properly attribute information when it comes to writing the paper.

4. Common knowledge trap

Authors may find it difficult sometimes to tell the difference between common knowledge which they are free to use, and original ideas which are the intellectual property of others.

What is common knowledge?

Facts that are readily available from numerous sources and generally known to the public facts and are not the result of unique individual research are considered “common knowledge,” and are not protected by copyright laws. You can use these facts liberally in your paper without citing authors. If you are unsure whether or not a fact is common knowledge, you should probably cite your source just to be safe. How to prevent plagiarism?
The Alexandria Initiative on Scientific Misconduct: Plagiarism which is available on the Medical Research Institute web site (www.mri.edu.eg) entails many points that can help institutions in preventing plagiarism. What is needed in order to prevent or minimize the number of plagiarized articles is a balanced approach that combines appropriate use of awareness campaigns and educational programmes against a background of clear, fair and effective disciplinary procedures. Such an approach should include the following:
1. Minimizing opportunities for plagiarism
2. Awareness campaigns on plagiarism
3. Teaching skills that help avoid plagiarism
4. Creating a climate that discourages scientific misconduct
5. Use of electronic soft ware that helps in detection of plagiarism
6. Fair, clear and consistent disciplinary procedures
7. Setting out key figures involved in such disciplinary procedures and their roles
8. Informing students, academics, authors about institutions and journals policies and practices in tackling plagiarism.