Using sources is important when writing research papers because they help support your ideas and make your paper stronger. Good sources include books, academic journals, and trusted websites. When choosing sources, check if the author is an expert and if the information is up to date. To avoid plagiarism, always give credit to the original author by citing your sources correctly. You should use quotes or paraphrase information but still mention where it came from. Tools like plagiarism checkers can help make sure your work is original. By using credible sources and citing them properly, you can write a strong paper and avoid any problems with plagiarism.