New and unsure how this works?

You can use as much or as little as you like. When I first joined it had not registered that it was anything more then an app, until I logged myself out on my ipad and remembered I actually had to sign up on the computer to make an account. I would see my newsfeed of all my own activity and thought I had to "know" people using the same app. I did not visit the actual site for quite a few months in the begining, now I use both back and forth to track calories. I then found the forums and adding friends with similiar goals and habits, it does help to have others learning and using things you might like to try, getting opinions, etc. I work from home as does my husband, I try not to bore him too much with all my talk, though he is amazingly supportive, it is not the same as someone else my own age, weight or whatever who knows EXACTLY what I am talking about.

Good luck, I love MFP as I know I must log everything to keep getting results, and most likely will have to do this forever in some capacity to maintain. I had lost in the past with WW but as soon as I stopped logging, I fell off fast. I knew the keeping track was key which is why I did this, free, no fitting meetings in and made sense for my life now. I try to recommend to everyone, though with weight loss sometimes people have to find their own way or motivation. Check out my profile if you think we'd make good pals feel free to friend me.

I suppose its a little like facebook! Add friends see how they are getting on, post how you are getting on, support one another aswell!
You can use it just as tracking your food and excersise without adding friends. But i only signed up for friends last night, i kind of feel like i'd be letting someone down if i go over my cals for the day haha!!