This interactive website will help you to understand the fretboard of any kind of guitar in any tuning. Accoustic or electric guitar, ukulele, bass guitar, banjo and mandolin; this website covers all of them. Switch to different scales, modes, instruments or tunings to compare when you want to. The website gives you nice overviews of all notes and scales, how intervals works and how to deeply understand them. So, if you want to dive deeper into your instrument, grab the instrument and play along!
Chord progressions are series of two or more chords used in a piece of music. Chords and arpeggios are basically the same, but arpeggios are created from chords notes but played one note at a time. Chords are played together and strummed. Triad chords are using the interval 1,3,5 but are shifted over the scale, so have different starting position. If the chord is major, an uppercase Roman numeral is used. If it's minor or diminished, a lowercase Roman numeral is used. To distinguish diminished from minor, a degree sign is added to the lowercase Roman numeral for diminished.
The lack of (a minor or a major) 3rd in a chord creates an open sound while the dissonance between the 4th and 5th and root creates tension. A suspended 4 chord is using the interval 1,4,5. A suspended 2 chord is using the the interval 1,2,5.
Power chords are using the diatonic intervals 1 and 5: the root note (tonic) and the fifth (dominant). Power chords are neither major or minor because it is lacking the 3th (mediant).