This is the floor. Eight bars, a single digit in each, and not one other mark anywhere on the page — the version of a number chart that a writer produces when the arrangement holds no surprises and the band can be trusted with everything else. It is also, by a wide margin, the most common thing anybody is handed.
Read it as eight equal boxes of four beats. The digit in a box is the chord for the whole box; the boxes go left to right and the page wraps like text. There is no repeat structure declared here because there is nothing to repeat yet, and there is no key, which is the part that takes getting used to.
Below, the same eight bars in G and then in C — a fourth up, the single most common move a session makes to a written page. The middle column is what is actually printed, and it is the column that does not change.
| Bar | Written | In G | In C |
|---|---|---|---|
| 1 | 1 | G | C |
| 2 | 1 | G | C |
| 3 | 4 | C | F |
| 4 | 1 | G | C |
| 5 | 5 | D | G |
| 6 | 4 | C | F |
| 7 | 1 | G | C |
| 8 | 57 | D7 | G7 |
What the plain version already gives you
Look at the two realization columns and notice what did not change: the numbers. The page on the stand is identical for both, and would be identical for the other ten keys as well. A singer who wants it a tone lower gets it a tone lower with no pencil work, no reprinting, and no negotiation — which is precisely why a room full of professionals writes music this way and why nobody in that room finds it clever.
The last bar is the only one carrying a mark, and it is the mildest one there is: a 7 on the 5 chord. That is the writer saying the dominant seventh is part of the arrangement rather than a taste decision — a small enough thing that half the room would have played it anyway, and worth writing precisely because the other half would not.
Everything else on this site is an addition to this page. The next chart divides a bar; the one after it moves where a chord lands. If reading this one is still slow, none of that will help — the drill will.