I had my eye doctor write me a prescription for some, last time I got my eyes checked. Been wearing bifocals for ~7 years now, and was noticing that most of the time, I was sitting too close for the distance lens, and it's too big a pain to tip your head back to use the reading lens (at the bottom of the distance, or "normal" lens). Had him set it for a focus of 2-4 feet.
I find myself not using them, though, because when I have to get up and do something, and put my regular glasses back on, it really strains my eyes to get used to focusing for distance again, for the first minute or two. Strangely enough, it was actually easier to just adjust my distance from the screen, with my bifocals on, until it was "good enough" to be able to read. Of course, I don't keep my resolution up so high that I'm struggling to read tiny looking fonts either!
Mind you, I've worn glasses for ~40 years now. Might be a different experience for someone who doesn't wear glasses, or only wears them for reading.