Before you start buying and riding a skateboard, let's define what a skateboard is and what it is made of.
A skateboard (or skateboard!) is a wooden board mounted on axles on which the wheels (themselves equipped with bearings) turn.
Most of the time, the skateboard is used in"Street", that is to say to make figures on the flat or on modules in a skatepark.
Skateboard: Tray
A skateboard is above all made up of a deck. It is a wooden board (most of the time made of 7 layers of maple) raised on each side to do tricks. The raised ends are called the tail and the nose . The tail is often shorter but there are also many "Popsicle" boards: which are perfectly symmetrical. Often, you can recognize the direction of the board by the design or the logo that is drawn underneath.
All boards also have a concave. The concave is the curvature of the board across its width. The more concave a board is, the more "wedged" you are on it. A deck is more or less concave (weak, medium and strong). Most (bare) decks, and almost all complete boards offer a medium concave.
Note that the concave allows the skateboard to be much stronger than if it was flat. There are almost no flat boards anymore, except for some Old-School boards that are reissues of old models.
Skateboard: Trucks
The trucks are the metal axles on which the wheels are fixed. The trucks are screwed in the plate. They are composed of a base on which is mounted an axle that pivots on rubber, which allows to turn.
The size of the trucks is normally related to the width of the plate. The longer the axles, the more stable the skateboard will be. This is one of the reasons why a skater may opt for a wider skateboard deck: to gain stability.
Most of the time, there are at least two main families of trucks in the range. The classic ones have solid axles and are the heaviest. The "Hollow" or "Light" have hollow axles and are therefore lighter (and more expensive). Depending on the brand, there is an ultimate version, the Titanium Trucks, lighter and stronger!
The rubber on which the axle pivots (or bushings) are made of plastic and can vary in hardness (called Duro). Heavier skaters will want to go up in hardness to get a more stable board.
Skateboard: Wheels
The classic skateboard wheels are quite small, and very hard. These are the wheels that equip the boards of street in general and their diameter is often between 52 and 54mm. There are different shapes ("Shape"), different hardness and different diameters.
We can vary these parameters to build a board dedicated to a particular practice. It is the case for example of the skaters who wish cruiser (to move with the daily newspaper or to walk) which will privilege larger and softer wheels. A bigger size will allow them to make less efforts to maintain their speed, while a lower hardness will offer more comfort against the roughness and defects of the ground.
Skateboard: Bearings
Each wheel is equipped with 2 bearings (8 in total on a board). These are the bearings that ensure a good "rollability" of the skateboard, a good glide.
Skateboard bearings are one of the main consumables on a board. Depending on the maintenance you do, you can extend their life. You must avoid riding in water at all costs to avoid seeing your bearings oxidize.
All the bearings are compatible with skateboard (and longboard) since all the axles of trucks measure 8mm in diameter.
Skateboard: Grip
The grip is the abrasive surface that covers the top of the board. It is usually a black adhesive strip that is glued to the wood.
However, there are many models of grip that can be used instead of the original grip (which must be changed when it does not stick anymore).
The grip allows the skater to "hang" on its board. It is very useful to avoid sliding all the time and especially to do tricks that require "scratching" the board to make it turn (like the kickflip for example).