A chord's name is determined by it's root note. Like for a B major chord, you would have (please know I'm running over to the piano to check this...) a
B, D#, F#. An inversion of this chord would place the F# at the bottom, making it
F#,B,D#, and one more inversion would be
D#, F#, B. All three of these are B chords, only different inversions. The way you tell (the way I do it) is to continue to swap the notes around like I showed until they are all every other note, and then find the root (lowest) note.
C, E, G
C chord, because the notes in the chord are all every other note (one note separates each neighboring note in the chord.)
E, G, C
C chord. As shown above, the notes are not all separated by a single note (
E are separated by 2 notes, not one), so you would swap the notes until all the notes are separated by a single note (i.e.
E carousels to the top of the chord, then
G(at the bottom of the chord) moves to the top) and then you have
C, E, G again. Now all the notes are the same distance apart, and this is therefore root position. You look at the first note (
C) to get the name of the chord.
For more info on more complex chords, please see My Music Theory.com
(EDIT, Just caught a mistake in my second example of the inversion, where I acted as though it was a second inversion while it was a first inversion)
Ok, let's see. I understand you're playing guitar. I frankly know nothing about guitar, but music theory is the same everywhere. A good way to visualize it is with a piano keyboard, so here's an image:
So, if you were to play a straight up
C chord, you would press the
C, E and
G keys. Note that they are every other note on the keyboard. The
C is your root, so to build a chord, you start with your root and then hit every other note. Now, an inversion is simply moving the bottom note (in the case of a straight up
C chord in root position, it would be the
C) to the top of the chord. It's still a
C chord, but the notes are in a different order.
Here's a handy image of a
C major chord in its first inversion (
C moved to the top)
As you can see, the notes aren't all the same distance apart. If you move the bottom note to the top again, you get the second inversion.
Here's an even handier image showing all three inversions (root, first and second):
So, on a guitar, you have...
If you take any three notes in this chord and carousel them around enough (in the correct order, of course) you will get your root C.
Hope this helps, good luck!