Sketch summarizing the results on the taxonomical analysis of 58 protoplanetary disks in scattered light. The top panel emphasizes the young age of faint disks and the old age of spiral disks relative to the respective PMS stellar lifetime. It also highlights the space of stellar properties that is not covered by the currently available sample. The bottom panel sketches theshallow trend of the dust mass with time for the transition disks that are typically observed in PDI.