The most popular and easiest to get started RVing type of RV is called the travel trailer.
The biggest distinguishing characteristic of the travel trailer is that it is hitched directly to the bumper of a pickup or SUV.
If you HAVE a SUV and want to use it to tow an RV, the the travel trailer is your best choice. A downside of the travel trailer is that you MUST be very mindful when towing it as the hitch configuration can cause some instability in certain towing conditions (wind, speed, situational).
I actually don't known the numbers, but this RV is the most plentiful and common. They range from small car towable designs to very large models that rival, well almost rival, fifth wheels. Puma is a travel trailer. These have a straight design – they look like a loaf of bread with a hitch that comes out directly to connect to a hitch on the bumper ( or thereabouts ) on a pickup. Because of this hitch, no special equipment is needed other than a “ball” on the bumper.
This convenience of a bumper hitch *AND* most of the conveniences of home makes this the RV of choice for most families.