general

This is a typical example of a chord result. The picture contains the following elements:

dark blue squares are fingering positions.
light-brown squares are possible fingering positions: all notes on the fingerboard that fit in this chord.

Strings are colour coded:
blue strings should be fretted.
green strings are played open.
red strings should be muted.

roman numerals under the fingerboard represent the position of the chord.

letters at the side of the strings correspond to the notes that will be heard on each string, where an X indicates a muted string.
letters in parenthesis at the side of the strings correspond to the open tuning of that string.

cord name and information is shown at the top of the picture.
If this information is dark blue, the chord was calculated with all notes present.
If this information is red, the chord misses one or more notes in this configuration. The notes that remain, however, are correct for this chord.

C[1]-E[2]-G[2] in this example means that one string will sound as C, two strings as E and two strings as G.
 

root

Here is where you choose the root for the chord.
So, if you're looking for a Dm(maj7), you choose D here.
At this moment, all notes are notated as sharps, even though in some occasions flats would be better (for example, a C7 chord should contain a Bb and not a A#, which is how it is notated at this moment. This will (probably) be changed in a future release.
For the sake of being complete: C# = Db, D# = Eb, F# = Gb, G# = Ab, A# = Bb (with C# = C sharp and Db = D flat).
 

type

Here is where you choose the type for the chord.
So, if you're looking for a Dm(maj7) chord, you choose m(maj7) here.
As can be seen, a lot of chord types are available. They are presented in an array in which types in any row or column have at least one parameter in common. So, all major chords are grouped together, as are all dominant 7 chords. There are always some wildcards, however. If chords stand on their own they are separated from other chords in the array by a thin line.
There is a complete list of all chords that are supported by the application at this moment.
 

position

Here you choose the position at which the chord is played.
Different players have different definitions for position, but I used the following:
Position 0: The chord may contain open strings as well as fretted strings (typically up to the 5th fret).
Position I: The chord only contains fretted strings starting with fret 1 with a maximum stretch of 5 frets.
Position II: The chord only contains fretted strings starting with fret 2 with a maximum stretch of 5 frets.
etc.
 

calulation method

This option defines how the chord is calculated.
first come first get chooses the notes that have the lowest possible stretch. This means, for example, that the Cmaj7 chord will have a B on the 5th string instead of a C, which would be more logical. But since the B is located at the 2nd fret and the C at the third, the B is chosen as the winner!
from the bottom up will calculate the chord from the bottom up as much as possible. This means that first the root is given a string, then the second note, then the third, etc. So with this method, the Cmaj7 chord will have it's root (C) nicely fit at the 5th string. This method will result in more precise calculations, but the stretch will generally be a little larger.
 

open strings

When this option is checked, the chord will contain as many open strings as possible.
One side-effect of this is that there is chance that some notes will no longer be included in the chord, because the open strings have preference to them. However, using this option in combination with high positions will give some interesting patterns that are great to use in supporting parts for fingerstyle arrangements.
 

root as lowest note

When this option is checked, the chord will have its root played as the lowest note.
All strings below the string that contains this root will be calculated as "muted". For example, in standard tuning, a D chord with "root as lowest note" checked on will have the 5th (A) and 6th (E) string muted. The same chord with "root as lowest note" checked off will have an open 5th (A) string and a D note fretted at the 2nd fret on the 6th (E) string.
 

left/right-handed

This option allows the player to choose between left-handed and right-handed chords.
The chords themselves are of course identical, but are displayed in such a way that left-handed chords will look natural to the left-handed player and right-handed chords will look natural to the right-handed player.
And for once, the left-handed option is chosen as the default. Just to let the majority know how it feels.
 

help

This option opens the Chord-o-Matic help screen.
But wait: if this option accidentally does something else, you would never get to see this explanation, and would never find out what the option was supposed to do in the first place. Welcome to the Twilight Zone.
 

feedback

This options opens a form in which you can give feedback about the application. So, if you're missing chords, the application isn't working as it should, or you have some other idea, please use this option. The guitar playing world will be a better place for it.
 

string tuning

These 6 pop-up menus represent the tuning of the strings on the guitar. The highest menu represents the highest string, etc. Each string can be tuned to standard tuning (which is the default setting), up to 2 steps higher and up to 2 steps lower. This means that the lowest E string cannot be tuned done to a C and up to a G#, but not to an A. While this will never happen in real life, one can imagine a player that wants to tune his guitar as, for example AADEEE. At this point, Chord-o-Matic doesn't support these super exotic tunings. If enough people think that it should, it will probably be changed.
 

reset

This button resets all parameters of Chord-o-Matic to their default settings.
This will result in a Cmajor chord, position 0, left-handed, tuning EADGBE.