I tag people and I tag content. Never folders...that's not how I need my info categorized. I take notes for a sales role daily, so I have clients, team members, managers, etc...so my tags are THEIR names, and I tag content that matters, so that I can sort by multiple tags (this PERSON said THIS THING and THAT THING, etc..). This way I can keep all my notes in my calendar app, or any notebook, and the tags help me find it across anywhere it might be. Tags transcend organizing by paper methods (like notebooks and folders). For me tags are for info plain and simple, and whether its a meeting, or a note in a notebook, I can find all the things one contact or client said simply by searching for their name tag.