Common techniques are shown visually. They are included when they are an integral part of the shape.
Place one finger over the notes.
Slide between the two notes.
Hammer-on and/or pull-off between the two notes.
Bend the note in the direction shown. The distance to bend (half step, whole step) can be seen in "tones" view.
Sets of notes that are often played together. This needs a better description.
Open position chords show both open and muted strings.