2- Family inet , bridge , ethernet-switching and other

https://www.juniper.net/documentation/en_US/junos/topics/reference/configuration-statement/family-edit-interfaces.html

Family bridge is used when you want a port that has more than one logical unit, each with the same or different encapsulations. Bridge domains are associated with GRE interface with the corresponding BD VLAN.

ethernet-switching   only one logical unit