Percussion mallet

A percussion mallet or beater is an object used to strike or beat a percussion instrument in order to produce its sound.
The term beater is slightly more general; A mallet is normally held in the hand while a beater may be foot or mechanically operated, for example in a bass drum pedal. The term drum stick is less general still, but still applied to a wide range of beaters. Some mallets, such as a triangle beater, are normally used only with a specific instrument, while others are used on many different instruments. Often, mallets of differing material and hardness are used to create different timbres on the same types of instrument (e.g. using either wooden or yarn mallets on a xylophone).
Some mallets, such as vibraphone mallets, are normally just called mallets, others have more specialized names including:
Types.
Drum sticks.
Drum sticks are beaters normally used in pairs, with each held in one hand, and are similar to or derived from the snare drum sticks that were subsequently adopted for kit drumming.
They are the most general-purpose beaters, and the term covers a wide variety of beaters, but they are mainly used for untuned percussion.
Mallets.
As well as being a general term for a hand-held beater, mallet is also used specifically to refer to a hand-held beater comprising a head connected to a thin shaft, and used in pairs. There is a wide selection of mallets to choose from to create a desired sound, articulation, character, and dynamic for the pieces being played. Professional percussionists typically have a good selection of mallets on hand in order to be prepared for each piece. 
There are three main types:
Mallet shafts are commonly made of rattan, birch, or synthetic materials such as fibreglass. Birch is stiff and typically longer in length, while rattan is a more flexible shaft and gives a more open sound. Fiberglass is ideal for playing lightly on an instrument because it is easy to control.
Different mallets are used primarily to alter the timbre of the mallet instrument being played. Generally, mallets composed of softer materials will stick to the instrument for longer as they bounce off of it, which gives a deeper sound made up of lower frequencies. Harder materials tend to bounce off quicker, and as they stick to the instrument for a shorter amount of time, they tend to be able to excite more of the higher frequencies, giving the sound a higher pitch with more overtones. Mallet choice is typically left up to the performer, though some compositions specify if a certain sound is desired by the composer. 
Players frequently employ two mallets in a matched grip or four mallets in a four-mallet grip; however, use of up to six mallets is not uncommon. More than two mallets may be used even when no chords are called for by the composer so that the performer has a wider range of timbres from which to select or to facilitate performance of music that moves rapidly between high and low, and if hit properly can switch between the two pitches.
If the mallet is too hard, the instrument may be damaged. For example, on rosewood marimbas, certain mallets may be too hard, increasing the risk of a cracked bar. 
Brushes.
Brushes are a set of bristles connected to a handle so that the bristles make a rounded fan shape. They are often used in jazz or blues music, but also in other genres such as rock, country and pop. The bristles can be made of metal or plastic; the handles are commonly made of wood or aluminum, and are often coated with rubber. Some brushes are telescoping so that the bristles can be pulled inside a hollow handle and the fan made by the bristles can be of variable length, width and density. Retracting the bristles also protects the brush when it is not being used. The non-bristled end of the brush may end in a loop or a ball.
Rutes.
A rute or multi-rod consists of several thin sticks that are bound together to form one stick. Its sound is midway between a stick and a brush.
Long used in orchestral music, in the mid 20th century rutes also became popular for many other purposes including kit drumming and bodhrán.
By dissipating much of the energy of the stroke within the stick, a rute allows a drummer to achieve both a tone and a playing action that would normally be associated with quite loud playing, but at a moderate or even low volume. The tone produced by many can be adjusted by adjusting the position of one of the bands holding the bundle together.