#1
Can someone please explain these to me. They have to do with chords, but I just don't understand what they are what they are for. Thanks!
#2
I = 1
II = 2
III = 3
IV = 4
V = 5

?? They can do with anything, notes relative to a key, notes in a mode, chords relative to a key, notes relative to a chord

be specific where you saw them
#3
It allows musicians to notate the same chord ideas in relative terms, like D G C is the same in relative terms as G C F, kind of like a musical algebra. Also lowercase numerals indicate a minor chord.

EDIT: Quite simply, they're used to indicate the chords in relation to the root chord of the key.
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#4
Useful in notating a chord progression without being limited to one key.

example: I IV V could be played in any key.

also , lower case specifies minor vi , upper case major IV, thus minor six chord and major four chord.
#5
Playing classical string instruments, it means what position you should switch to to play the notes...
#6
Quote by Shackman10
Playing classical string instruments, it means what position you should switch to to play the notes...


But we are on a guitar forum, and classical string players would know this allready. All the thread starter needs to know that the roman numerals are used in diatonic [seven tone scales] harmony to indicate which scale degree the chord is based upon.
#7
Playing classical string instruments, it means what position you should switch to to play the notes...


that is a far less common question, and people who ask about that(or other less common usages of roman numerals) tend to be a bit more specific.