Plagiarism is the representation of another author's language, thoughts, ideas, or expressions as one's own original work. In educational contexts,
The Common Types of Plagiarism
Direct Plagiarism. Direct plagiarism is the word-for-word transcription of a section of someone else's work, without attribution and without quotation marks.
Self Plagiarism.
Mosaic Plagiarism.
Accidental Plagiarism.
Guidelines to avoid plagiarism
Understand the context. Do not copy–paste the text verbatim from the reference paper.
Quote. Use quotes to indicate that the text has been taken from another paper.