Trailers are non-powered (except for lights and brakes [if braked]), and non-steered. They are dragged by your vehicle and your vehicle must be capable of handling the weight and characteristics of the trailer. Independent of vehicle type and what type of box trailer you are towing, your vehicle is affected by various influences for which you need to be aware of for your own safety, as well as the safety of other users of the road.
Wind is a factor that can catch you off guard and can cause serious steering and stability problems. This is more pronounced on a high-sided trailer, which when caught by a strong gusts of crosswind can move the towing vehicle by a considerable margin. This can be felt when you are briefly sheltered by crosswinds (to which you have adjusted your steering) like from a passing truck or in a tunnel and then again exposed to the wind which can catch you off guard and may throw the vehicle off balance. This should also be considered while passing by buildings which may provide considerable shelter from crosswinds. Headwinds are to be considered when carrying tall loads that can catch the wind. In this situation the acceleration of the vehicle is affected. This is also important when going uphill which can cause a rapid loss of speed and potential stalling of the vehicle.
Driving while towing a trailer can also be affected by the surface on which you drive on. The suspension on a trailer is much less sophisticated than compared to a car, and significant bumps can cause stability issues and bump-steering, or the load may be shifted. While driving on a rural unpaved road can be predictable and by itself require slower speeds, driving on paved roads can be quite challenging especially if there is a possibility of uneven terrain and bumps and crevasses on the surface.
The type of load can also affect how the trailer performs, and ultimately how the towing vehicle behaves on the road. Low and static loads are the easiest to pull. This is because they have a low center of gravity which is always stationary. Tall loads no matter how secured they are, have a high centre of mass which is more susceptible to cornering forces and can cause you to lose traction and rolling over if entered a curve with higher speed. Towing live animals requires the ultimate in dexterity and vehicle handling skills, because every time the animals move, especially big animals like horses and cattle, you will feel it.