Equipment
Rackets
Badminton rackets traditionally were made from wood. However as they have evolved over the years they have gone from wood to steel and now are made from lightweight strong materials such as carbon fiber and nano-technology. As the game has gotten faster and faster, the rackets have adapted to give the players the speed they require while still providing the power.
Rackets nowadays weigh between 70 - 90 grams. In general, a heavier racket is more for power play while a lighter racket is more defensive. However more often now we see rackets being produced that try to strike a balance between the two. A players choice of racket may depend on may things, such as whether they play singles or doubles, whether their game is more offensive or defensive and of course price.
In particular rackets at the higher end of the market will often be advertised as head heavy or head light. A head heavy racket, as the name suggests, in one in which the balance point is lower down the racket so there is more weight towards the head. This generates more power as there is extra weight behind the shot. The opposite is true of a head light racket. However the lack of power is compensated with better a defensive ability and faster maneuverability in and around the net area.
Historically Yonex has been considered the benchmark for quality rackets however in recent years other companies are becoming more prominent through sponsorship of top class national teams. For example Li-Ning and Victor sponsor the Chinese and Korean national team respectively.
Shuttles
Shuttlecocks can either be plastic or feathered. Normally at the recreational level you will see plastics more often being used, where as at most clubs and in competitive play, feathered shuttlecocks are used. The feathers are taken from only the left wing of a duck or goose. Goose feathers offer a higher quality than duck feathers.
Plastic shuttles were developed due to feathered shuttles being eaily broken several times in a game, which is expensive for the recreational player. Plastics are much cheaper and more cost effective as they last much longer than feather shuttles. Feathers may last only one or two points depending on the players ability to strike the shuttle cleanly and consistently.
Feather shuttles are generally prefered among the badminton community as you can feel and control your shot more accurately. They are also better in order to prevent shoulder or elbow injuries. Many people tend to try and force their shot when striking a plastic, where as a feather feels much more natural to strike.
There are many different quality shuttlecocks both with plastics and feathers. When buying, it is important to research the plastics which most fly like a feather. There are three different speeds of plastic shuttle, Blue, Green and Red. These are slow, medium and fast respectively.
When buying feathers it is important to buy a quality brand. Most elite tournaments use Yonex shuttles, which are considered the best quality shuttles.
Shoes
Many people mistakenly believe that the racket is the most important piece of equipment for playing badminton. This is a mistake. The more important thing by far is the correct foot wear. Wearing the right shoes for badminton allows the correct support specifically for badminton movement. In particular the ankle is heavily supported due to the high amount of lateral movements involved. In addition the sole of the shoe is lower to allow weight to spread a little more over the area of the shoe and lowers the centre of gravity.
It is important to invest in a good quality pair of badminton shoes. Playing in running shoes, as many beginners do, is not a good idea as it can lead to sprained ankles and possibly worse injuries. They do not provide the support required for the movements of the sport.
Grips
Badminton grips are used in order to gain more comfort from the handle of the racket. Badminton rackets come with an undergrip already attached to the racket. This is very thin and just covers the wooden handle. The main grips you see commercially are the towel grips and the rubber grips which are made from polyurethane. The towel grips are more often used by the professionals as they absorb sweat. The rubber grips offer a tacky feeling, as if the racket won't come loose from your hand easily. It is your preference as to which one you prefer.
You can also put on two or three grips, depending on what you find comfortable. A thicker grip may suit some more than others. Thicker grips however may disrupt the switching of grips in a game, where as a thinner grip would allow more comfortable transition, for example from a forehand to backhand grip. Thicker grips however may favour those with elbow issues. Thinner grips offer the player more maneuverability in their racket movement. It would suit a more deceptive, wristy player. It is a subjective matter and up to the player to decide what best suits them.
One last important thing to note is that grip size may affect the balance of the racket. As you put a thicker grip on, the balance point moves further towards the head of the racket.