2018.01.17; Daniel Borhanian shared an answer on Quora with you

Tags are a useful way of organizing a series of notes into a sub-topic, where each note in the sub-topic does not contain a word that would pop up in a notebook-wide search. They are also useful for tracking information that is spread across multiple notebooks.



A past Evernote podcast addressed this topic directly, and the hosts described tags as being useful for organizing information within topics that aren't broad enough to require their own notebook. Think 'vegetarian' for notes within a Recipes notebook, or 'Expenses' for documents you might use to put together an expense report from within a Work notebook.



If you were gathering information about tablet computers, your notes would have words like "iPad" and "Playbook" and "Galaxy Tab" in them -- but not necessarily a word like "tablet" that would ensure they all pop up in every search. A search for 'tablet' might also bring up false positives -- a doctor's note instructing you to take two tablets a day of a particular medication, for example.



Tags allow you to review all of your notes at on a given subject at once, or see them at a glance. In the above example, by adding the tag 'tablet' to your notes on the iPad and its competitors, you will then be able to click the tag in Evernote's sidebar and all your associated notes will materialize for easy scanning.



That said: There's no reason to create tags for topics you don't regularly return to, and creating a glut of them will clutter up your sidebar. As with most software, the fewer tags you can get away with using, the better.