Its called a blower motor. it is underneath the passenger side off the dash behind the glove box. Take a small hammer and with the blower motor in the on position tap the blower motor with the hammer a few times if it starts to run then the brushes are bad in the motor you will need to replace the motor. You possibly could have a bad fan speed switch, Try taking some compressed air and blowing it through where you move the blower switch from side to side then spray some WD-40 in the same area and move the switch side to side several times.