Dividers are lines which helps separate content into groups inside lists and layouts, or create separation inside the same content.
Plain dividers creates hard separation to group different lists and layout. They are used as a partition to separate content into groups. They are used when the content to be separated is significantly different from each other.
Dotted dividers creates soft separation inside the same content group or to stitch multiple content. They are used to separate things in groups inside same content or layout. or to stitch different contents together.