There are three main types of cargo bikes:
Children and other cargo can be carried on an extended rear rack that sits over the back wheel. They're popular among families with more than one child. A child seat can be mounted on this rack or a bench can be mounted on it.
Compact utility bikes are shorter than longtails. Some of these bikes are about the same length as a standard bike, but are more capable of hauling. Many can be stored, transported, and folded. For larger families, they may not be as versatile since they may not be able to handle multiple kids.
Front-loading cargo bikes
You can transport your cargo in a box or container that sits low between the handlebars and the front wheel. Families like these bikes because they can carry pets and kids in the front where they can keep an eye on them, and conversations are easier. Although they take some practice to ride, they're surprisingly easy to maneuver.