Parents: Did you send your children to daycare/preschool (something other than an informal babysitter) and if so, at what age did they start?

My daughter just turned 3 about 3 months ago. She has been at a babysitter since she was 7 months old, when i returned to work. I love this babysitter, she’s great, reliable, clean, easy, all great things. My daughter goes to babysitter’s 3 days a week and 2 days to my mom’s house. I just signed my daughter up for two days a week to a preschool. That would be one day from the babysitter and one day from my mom.

I am just curious when other parents started their children in day care/preschool, or did you use a regular babysitter until kindergarten? or did you keep the child home with you until kindergarten? or did you use the pre-k in lieu of kindergarten?