Has anyone heard of a meet and greet?

My sisters are throwing me a meet and greet. It’s a diaper party/ shower that will be held after the baby is born. So people can meet him and enjoy a fun day. I’m excited but nervous at the same time cause I never even heard of this before. Hard part is not posting pics and only letting immediate family or friends see him until the party. Which is totally a choice but I thought would be more interesting..