Those lines are used for estimating depth of field.

If you don't know what depth of field is - google it first or it'll get confusing

If you want to use those lines, here's how it works.

If you count from the center, there are 5 pairs of lines, the middle pair is orange.

Below the lines, there are several aperture markings, also in pairs except for the middle one - the rhombus, which represents aperture of f/3.5 (the largest aperture of your lens). Each pair of lines corresponds to a pair of aperture markings, except for the innermost orange pair, which corresponds to the rhombus. The second innermost pair of lines correspond to aperture f/5.6, the third innermost pair corresponds to f/11, the next pair corresponds to f/16, and the outermost pair of lines corresponds to f/22. (it's kind of hard to explain but really easy once you get it

)

Now, say, you're using your lens at some aperture and you want to know what depth of field the lens will give you - without actually taking a picture. To estimate the depth of field, you just look at where the pair of lines that correspond to the aperture you've selected point on the distance scale (top of the picture).

For example, if you're using f/3.5, you would just check the innermost orange lines - which right now point at 3m and somewhere between 3m and infinity. If you take a picture with aperture at f/3.5, everything from 3 meters to somewhere between 3 meters and infinity (distance from camera sensor) will be in sharp focus.

Say, you now want to use f/22, and want to guesstimate the depth of field. Now, you would check the outermost lines - which point at 1.2m and past infinity. This means that, if you take a picture at f/22, everything from 1.2m and onward to infinity (again, distance from camera sensor) would be in sharp focus.