I am having a rough time understanding the numbers on the chord.progression as an example on the C major scale. Why is it that they are boxed in these numbers ? And why those numbers ? Why in that particular order. I understand that I can find the chords in the scale, that is fine, but why is it in that particular order ? Can someone explain with plain simple words to me please ? 1 - C 2 - Dm 3 - Em 4 - F 5 - G 6 - Am
Chords made from purely the notes from a particular scale are numbered. Far more often though, using Roman numerals. Capitals for majors, lower case for minors. Your system is more commonly used in the Nashville Number System, which does use numbers, and was (and still is!) a very useful way to portray chords for songs, without actually putting them into a particular key.
Thus your '1' will be known as 'I', and is the tonic chord, on C, made up of 'stacked thirds', using diatonic notes. So, C E G. Your '2' will be 'ii', Dm, made up from D F A, and '3' will be 'iii', made up from E G B.
That makes the most used chords from any key - 3 majors and 3 minors. The chord made on the 7th note isn't major or minor - it's diminished, having m3 and d5. In key C, that's B D F, (viio). Not that commonly used, so sometimes missed out from the list of diatonic chords. Fairly clearly, the numbers reflect the root note number in any key. Thus IV (your '4') is F A C, based on the fourth note in the C scale, and major. I wonder what it was about the 'number system' that was confusing. It's pretty straightforward - it takes each letter name in the scale, and uses its numerical order number to name each chord.
Exactly the same method works for each and every key, so it's a universal 'one size fits all'.
This looks to me like the number is indicating on which scale degree the chord has been created.
Basically for each scale degree you can pick the corresponding note of that degree as your tonic and stack thrids on top to create a chord out of that scale degree. Here is some more information to read up on how to build chords from the scales.
In this case that would be the C (major) scale.
In my example i have used three notes per chord so I got the simple triads, but you can also use 4 notes per chord to create the seventh chords.
The seventh degree seems to be missing here... This looks to me like a list of the triads you can create from the C (major) scale and not a specific progression. Any source where you have that "information" from?
These numbers are describing the degree of the scale that the chord is based on. A major scale has 7 degrees and they are listed in order from one to seven. Each one of these degrees can become the root note of a chord using a formula of adding thirds on top of each other using the notes that are contained in the scale. A C major chord would be constructed by starting with the first degree of the scale, which is C. Then we would count up starting on the C, 1C,2D, 3E, the E is the third degree of this scale. This note is combined with the first degree to form a diad(two notes). Next we start from the third degree of the scale and count up the scale once again 3E,4F, 5G, G is the fifth degree of the C major scale. The fifth degree is added to the first and third degree to form a triad(3notes). This is the formula for constructing basic triads (chords) and this is why we need to number the degrees of a scale. This also comes in handy when we need to transpose a piece of music from one key to another. and this numbering system can be applied to both major and minor scales. A similar numbering system is widely used to describe the order of the chords in a scale using Roman numerals, with the major chords in a scale represented using Upper case numerals and minor chords are represented using lower case numerals.