Why is the standard tuning for the guitar E A D G B E, from the lowest string to the highest?
The interval between strings is a perfect 4th, except for the interval between the G and B strings, which is a major third. Then there is a perfect 4th between the B and E strings, so that the lowest string and the highest string are the same pitch, two octaves apart.
Is there any significance to this tuning? Is this a convention to make fingering chords easier?
This is a very good question. The answer is "because it's been done that way for centuries, as a result of the preferences of the majority of guitarists over the centuries".
Usually we list the strings by the lowest to the highest:
E A D G B E.
This tuning works very well for playing 4, 5, and 6-note diatonic chords (built on the three pitches in major and minor triads). Consonant sounds fall easily under the fingers.
However, there are many different ways to tune the guitar, some of which require using heavier or lighter gauges of strings, depending on the tuning. We refer to these other tunings as alternate tunings, or by their Hawaiian name, slack key tunings, or by their academic name in Italian, scordatura.
You can adopt any tuning you wish. However, if you wish to learn to play a particular piece of music on the guitar, it is best to use the tuning that the piece was originally written for. In most cases that is the standard tuning. But there are certain popular guitar pieces that were written in other tunings as well.
If you mean the relative tuning string by string, it's mainly for ease of use. There have been (and still are) many, many different tunings available, but this one must have become the 'standard' because with it, most chords are available to be fingered without too much trouble.The fact that most of us have four fingers on the fretting hand probably played a part - when soloing, in open position, every chromatic note for more than two octaves is available without moving your fretting hand up or down. In fretted position, it's still easy to play as such, with only a one fret move.
This 5-fret difference could have been continued onto the top strings, but would make barre chords pretty difficult. However, that pattern does go up, and down, with 5 , 6, 7 and even 8 string basses.
If you're asking about why have E as the lowest note, more difficult to say, except that it roughly follows the male human voice range (I'm talking open strings here, for all the castrati out there ! )
It could have been tuned in 5ths as violins are, but they need to be, as they only have four strings, with a much shorter string length making it difficult to play, say, up to its '24th fret' .
