At least two instruments called "guitars" were in use in Spain by 1200: the guitarra latina (Latin guitar) and the so-called guitarra morisca (Moorish guitar). The guitarra morisca had a rounded back, wide fingerboard, and several sound holes. The guitarra Latina had a single sound hole and a narrower neck. By the 14th century the qualifiers "moresca" or "morisca" and "latina" had been dropped, and these two cordophones were simply referred to as guitars.[8]
As their categorical name suggests, extended chords indeed extend seventh chords by stacking one or more additional third-intervals, successively constructing ninth, eleventh, and finally thirteenth chords; thirteenth chords contain all seven notes of the diatonic scale. In closed position, extended chords contain dissonant intervals or may sound supersaturated, particularly thirteenth chords with their seven notes. Consequently, extended chords are often played with the omission of one or more tones, especially the fifth and often the third,[92][93] as already noted for seventh chords; similarly, eleventh chords often omit the ninth, and thirteenth chords the ninth or eleventh. Often, the third is raised an octave, mimicking its position in the root's sequence of harmonics.[92]

There's no other instrument with as much presence and cultural identity as the guitar. Virtually everyone is familiar with tons of different guitar sounds, from intense metal shredding to soft and jaunty acoustic folk music. And behind all those iconic guitar tones are great sets of strings. Just like a saxophonist changes reeds from time to time or a drummer replaces sticks, putting new strings on your guitar every so often is an important part of owning and playing one.

I have heard how giving you are in so many respects of music schooling and I must say that I am impressed. You remind me of the pure idealism that we had in starting Apple. If I were young, with time, I'd likely offer to join and help you in your endeavours. Keep making people happy, not just in their own learning, but in the example you set for them. 

Learning guitar is a lot easier when you have a step-by-step system to follow. Guitar Tricks lessons are interconnected and organized to get slightly harder as you progress. You watch a video lesson, play along, and then click a “Next” button to go to the next lesson. Lessons have multiple camera angles, guitar tabs, jam tracks and everything else you need to learn.

The implementation of musical chords on guitars depends on the tuning. Since standard tuning is most commonly used, expositions of guitar chords emphasize the implementation of musical chords on guitars with standard tuning. The implementation of chords using particular tunings is a defining part of the literature on guitar chords, which is omitted in the abstract musical-theory of chords for all instruments.
In 1977, the Guitar Institute of Technology (GIT) revolutionized contemporary music education with the first full-time program to offer hands-on professional training for the electric guitarist. Over three decades later, MI remains the leader in guitar education, besting other colleges for guitar players, with a unique system that combines technical, creative and professional development in a performance-based program.