For those who are familiar with commas etc

For those who want to understand the diagrams quickly:
(When I say that a fifth is = - 60 TU, it means the fifth is 60 TU narrower than a pure fifth)
Horizontal line = a pure fifth (No green vector)
Line sloping downwards to the right ( = green vector pointing down) = a narrow fifth. (Very slope, very impure)
Line sloping upwards to the right ( = green vector pointing up) = a wide fifth.
The sum of all 12 fifths is always -720 TU = Pythagorean comma.
This number can easily be divided into 2,3,4,5,6,8,9,10
I have chosen horizontal line for pure fifths, which means that the diagrams are sloping down to the right. Although it's strange that F# ends further down than Gb, it is allright (for me) as Gb=F# is a matter of course on a keyboard with 12 tones per octave.
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A major third are measured with a red vector.
4 pure fifths C-G-D-A-E gives a pythagorean major third: C-E, the deviation from a pure third = 660 TU = 1 Syntonic comma.
This value (SC/ 660 TU ) can also be divided in 2,3,4.....
1/3 SC = -220 TU
1/4 SC = -165 TU
1/5 SC = -132 TU
1/6 SC = -110 TU
TU considered right is therefore very related to the oldest measurement unit for a fifth`s impurity: fractions of comma.
In 12-ET the major third = 420 TU (red vector)
A minor third is 
the vertical distance between red vector tip to green vector tip.
If you want to know the value (almost always negative) of a minor third, look for the note (for Em , look for a red E)  on the upper red graph, and then notice the vertical length of the red and green vector (from red vector tip to the green tip)
The exact value (sum) you will find  in blue lower in the diagram called   "vs equal (minor values)"
In 12-ET the minor third = - 480 TU (deviation from pure)
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To every tuning follows many diagrams.
A cent table follows where you can enter the values to an app like Cleartune, but where you now have the opportunity to choose your own variants after studying the diagrams.
Hope this was useful !