I found some ancestors identified as Criollos, Indio Criollos and Mestizos Criollos. Can someone please tell me if Criollo was a Spaniard born in the colones, why say Indio or Mestizo?

I found some ancestors identified as Criollos, Indio Criollos and Mestizos Criollos. Can someone please tell me if Criollo was a Spaniard born in the colones, why say Indio or Mestizo? Some are just Criollos, does this mean they were Espanoles?
Appreciate any explanation from this group to help me understand.