Hi there, I'm new to this but trying like hell to figure the basics of this out, (as I did a while back but failed, then went off and left it.) and was wondering if this is why there's 11 dimensions : 1. Height 2. Width 3. Depth 4. Time Then we move onto the stuff that causes many of us problems, but after reading up for a while I'm hoping (!) that I at least know why there's 11. Are these the extra 7? 5. Kaluza–Klein combination of gravitation and electromagnetism - 5th dimension. 6-10. 5 different string theories that all appear to be correct at the same time, leading to : 11. M-Theory, which says that the 5 string theories are all correct and part of the same thing, which adds 6 dimensions onto the other 5. I'm sure that'll be wrong, but I at least feel closer to working out how it's arrived at....the main confusing thing is : those 5 string theories from 6-10 are all supposed to be detecting 10 dimensions aren't they? So I'm sure I'm wrong, but if any of you could try and break it down like that, but with the correct info I'd be really grateful, because it's driving me half mad. I don't want to fail at grasping the very basics of the idea and then leaving it again either, then going off to learn about other things instead, because I'll only come back at somepoint in the future and get just as wound up again with the whole thing. 2nd post added to make it easier to merge if need be : Nobody? Ok, I just thought about it again a bit and I'm realising that I probably got it wrong with the 5 string theories. (surprise, surprise...) The 5 all say that there's 10 dimensions, but they're not numbers 5-10 like I stupidly thought, they're just 5 theories that add 5 onto the other 5, or 6 onto the 4 of length, width, depth and time. Then M-Theory comes along and says that they're all right, but only when you look at it from this 11th dimension, which as far as I can gather, can view the other 10 from different.....angles so to speak, and is something on a whole other level. Is that closer? But then that leaves me not knowing what the hell the other 5 are after the 4 and 5th that I listed earlier....will have to read up more.