Skateboard Truck Bushings
Bushing are are small rubber rings inside each skateboard truck. These Bushing allow your trucks to pivot and turn smoothly. There should always be two for each truck. The top bushing in each set helps keep to keep them turning smoothly. The bottom bushing can be tighten or loosen depending on how responsive you would like your trucks to be.
Bushing come different hardness compounds. Stiffer bushings will make your board more stable and can help with performing tricks and stunts. When it comes to just general riding and cruising the streets, a softer bushing will make turning easier and smoother. It will really comes down to how you prefer to ride. Harder for the skatepark and softer for cruising.
Skateboard bushings are a great way to change up the style of your board so you can have a number of different sets depending on how to feel like riding on any given day. They are relatively cheap so you won't break the bank if you decide to buy a few different sets of bushings.
Beginner set up boards tend to come with stiffer bushings just to make the skateboard feel more stable therefore making it easier to ride and learn on. It will make turning a little harder but the trucks and always be loosened off after a while once the user has gotten to grips with general riding.