O.K., here is a breakdown of chords symbols in sheet music and how to read them:
No Slash Chord Symbols
1. Chord symbol with just 1 letter signifies a major chord being played in the RH. It also says that the root is played in the LH:
C = C major chord (C-E-G / C)
2. Chord symbol with 1 letter and a lower case m beside it signifies a minor chord, root played in the LH:
Cm = C minor chord (C-Eb-G / C)
3. Chord symbol with 1 letter and a dim beside it signifies a diminished chord, root played in the LH:
C dim = C diminished chord (C-Eb-Gb / C)
*for fully diminished chord, the chord symbol is dim7: C dim7 = C diminished chord + added diminished 7th (C-Eb-Gb-Bbb / C)
4. Chord symbol with 1 letter and a aug beside it signifies an augmented chord, root played in the LH:
C aug = C augmented chord (C-E-G# / C)
5. Chord symbol with 1 letter and 1 numer beside it signifies the major chord plus the scale degree to be added, root played in the LH:
C7 = C major chord + added m7 (C-E-G-Bb / C)
C9 = C major chord + added m7 + added 9th (C-E-G-Bb-D / C)
C11 = C major chord + added m7 + added 9th + added 11th (C-E-G-Bb-D-F / C)
C13th = C major chord + added m7 + added 9th + added 11th + added 13th (C-E-G-Bb-D-F-A / C)
Cadd9 = C major chord + added 9th (C-D-E-G / C)
C6 = C major chord + added 6th (C-E-G-A / C)
6. Chord symbol with 1 capitalized M and a 7 signifies a major 7th chord, root played in the LH:
CM7 = C major chord + added M7 (C-E-G-B / C)
7. Chord symbol with 1 letter, an m, dim, or aug beside it, and 1 number signifies the minor, diminished, or augmented chord plus the scale degree to be added, root played in the LH:
Cm7 = C minor chord + added m7 (C-Eb-G-Bb / C)
Cm9 = C minor chord + added m7 + added 9th (C-Eb-G-Bb-D / C)
Cm11 = C minor chord + added m7 + added 9th + added 11th (C-Eb-G-Bb-D-F / C)
Cm13th = C minor chord + added m7 + added 9th + added 11th + added 13th (C-Eb-G-Bb-D-F-A / C)
Cm add9 = C minor chord + added 9th (C-Db-E-G / C)
Cm6 = C minor chord + added 6th (C-E-G-Ab / C)
8. Chord symbol with 1 letter and 1 or more numbers in parenthesis, but the added to the number is a flat (b) or sharp (#) signifiies what to do to the scale degree. A flat (b) means lower the added scale degree and a sharp (#) means raise the added scale degree, root played in the LH:
C7 (b5) (#9) = C major chord + added lowered 5 + added m7 + added raised 9 (C-E-Gb-G-Bb-D# / C)
Slash Chord Symbols
1. Chord symbol with 2 letters separated by a slash (/) signifies that the letter to the left of the slash is played in the RH and the letter to the right of the slash is played in the LH:
C/E = C major chord played in the RH + E played in the LH (C-E-G / E)
That's the only difference between a non-slash chord and slash chord. All the other rules of the non-slash chord apply to the slash chord. You can play chords any way you want, as long as the proper note is on the bottom. You can play all the other notes of the chord any way you see fit. There are even certain chords where you can omit a note(s) and still have the chord. I hope this helps!!!