The first glasses of my life -- I was in my mid-forties -- were bi-focals. I had reached the point where my arms weren't long enough to hold the newspaper far enough away to be able to read it. I adapted to them very easily. People warned me that I must be careful on stairs, curbs etc. but I had no problem.
My glasses now -- small, rimless, I love them -- have three gradations. The top, as always, corrects a minor astigmatism. I have very good long vision but the top just sharpens it. It's like fine-focussing a camera. The middle section is for my computer viewing. My optometrist says this helps me avoid tilting my head back and putting a strain on my neck. And the lowest part is for looking down -- for reading, eating, cooking, typing etc.
My glasses have no differentiating lines and the gradual change can't be noticed by others.
Having said all that, I had a problem once when I went to a "glasses store" because I just wanted to get a couple of pairs of less expensive rims, just for fun. They didn't do a very good job of interpreting my prescription apparently and I didn't really wear my fun rims that much. They gave me a headache. I find that getting my Rx filled with my optometrist has worked better for me.
