Predatory journals are unethical or low-quality journals that exploit researchers by requesting publication fees without providing legitimate peer review, editorial oversight, scientific quality control, or proper indexing standards. These journals often send aggressive email invitations, promise unrealistically rapid acceptance, use fake impact factors, falsely claim indexing in major databases, and publish manuscripts with minimal or no scientific review. Publishing in predatory journals may seriously damage the future academic reputation of researchers because such publications are often considered scientifically unreliable, may negatively affect academic promotion, grant applications, university evaluations, and future collaboration opportunities, and can reduce the credibility of the researcher’s scientific record. In some institutions, publications in predatory journals may not be officially recognized for academic advancement. Furthermore, these journals may disappear suddenly, remove published articles, fail to preserve scientific archives, or expose authors to copyright and ethical risks. Researchers should therefore carefully evaluate journals before submission and use trusted tools and databases to detect potentially predatory publishers. Important websites that help identify, evaluate, or verify journals include Think. Check. Submit., Directory of Open Access Journals (DOAJ), Scopus Sources, Web of Science Master Journal List, COPE (Committee on Publication Ethics), Cabells Journalytics, PubMed Journals Database, ISSN Portal, and Retraction Watch.