Several methods exist for you to stay up to date with the research in any particular discipline, whether that research is published via journal articles, books or on the web. No matter which method(s) you adopt, you’ll stay afloat in the sea of information.
Email alerts allow you to create a search and automatically rerun it in the database(s) of your choosing. Periodically you'll receive an email message -with links to abstracts or text- letting you know that new material has been published that matches your search query.
RSS feeds alert you when new content has been added to blogs, websites, databases, etc. that you follow.
Both methods relieve you from time-intensive searching so you can use your time to read, study, comprehend and use information to complete your assignments and research projects.
Q: Which method should you use?
A: Both methods are valuable. If the information resource offers both methods it's purely a matter of personal preference.