Hey there,

Materials can be classified as below:

1) conductor- the materials that conduct electric current fairly well :

Metals are the good conductor for example copper silver.

Range of resistivity 1/10² to 1/10 ohm meter .

2)Insulator- material which do not conduct current fairly well.Non-metals are good insulators for example glass, diamond. Range of resistivity is 10¹¹ to 10¹ ohm meter.

3) semiconductor- the materials which have resistivity between conductor and insulator. Silicon and germanium are typical semiconductor. Range is 1/10 to 10 ohm meter.

Hope it helps!