Resistors are widely used passive component. They are assorted by  function, shape, resistive material and its purposes.
 
Categorized by function, resistors are mainly classified to fixed resistor used in a electric circuit and variable resistor used as a radio volume by changing the resistance. Microhm's shunts are typical fixed resistors.
 
Fixed resistors are divided into lead type(with lead wire) and surface mount type without lead wire. Surface mount type includes rectangular type, such as Microhm MPR series, NMS series and cylinder type, like Microhm MELF resistor. Resistors are more divided into resin mold type and ceramic type etc.
 
The materials of resistive body includes more. Film type that includes carbon film, metal film, metal oxide film and  metal glaze composited by metal oxide and glass; metal plate, metal wire, those that apply metal foil; solid type that applies metal oxide ceramics.

 
The purposes of resistor are different depending on resistance tolerance, high voltage type, temperature characteristics,  surge resistant type, fusing type and temperature characteristic that changes resistance. We have to select a suitable resistor for our purpose depending on combinations mentioned above.