Guitar chord charts are one of many ways to visually show how to play (fret) guitar chords. It is a 'grid' of the fretboard with dots showing you where to place your fingers. Charts can also be called frames or grids or boxes. We have used grids for single chords less and less over the years.
The chord name will appear above the chart:
We will more commonly see chord charts oriented vertically, rather than horizontally (like above), especially in songbooks. Ultimately, once we know a chord, you don't need a picture of it, yet, sometimes the type of voicing for a particular chord in a song can be helpful when shown in a grid (typically at the beginning of a tune), sometimes inline, above the music.
We will sometimes see the fingerings inside the dots, or along the bottom of the strings, or myriad other variations of shapes and/or numbers. Vertical chord frames are most common, yet we think that there is a trend moving towards horizontal grids. This is mainly due to the fact that horizontal grids are configured in the same orientation as tablature & music notation (up is high, down is low). Consistency is a good thing.
It is also not difficult to look at a frame in any orientation, once we are familiar with it. We can turn it any direction needed. We recommend you move away from reliance on chord frames, & towards an internal referencing system (your library of fretted chords). Also, since chord charts are dominantly right handed, they are excluding left handed players, unless a given source provides a left handed version.
Chord & fretboard charts are very helpful in learning how things look visually on the guitar. We do recommend you print some blank grids, & map stuff out. Push a pencil, then move it to the hands, to the memory, & then to pure knowledge, or non-reference-point playing. These are simply maps, reference points, to use as a vehicle for non-reference playing.