Common examples of self-plagiarism include:
1. Submitting the same essay or assignment for two different courses without permission
2. Reusing sections of a previously published article in a new paper without citing the original
3. Recycling research data, results, or text from earlier studies without disclosure
4. Republishing the same blog post or article on multiple platforms as "new" content
Most universities, academic journals, and publishers have strict policies against self-plagiarism, and violations can lead to rejected submissions, retracted publications, or formal academic penalties. The safest approach is to always cite your own earlier work, just as you would any other source. Tools like Quetext help identify overlaps with previously published material so you can address them before submission.