State Ohm's Law and the main characteristics of ohmic conductors, giving examples

Ohm's law states V=R×I, which means that the voltage difference V across a component and the current I flowing across it are directly proportional one another, and the proportionality coefficient is the resistance R. This regulates that, for any ohmic component, the law is satisfied: knowing the voltage V and the resistance R it's possible to find the current I.Examples of ohmic components are resistors and wires, for which the V/I relationship is linear, whereas an incandescent light bulb doesn't respect this law. To understand this, it is important to note that any resistance is constant when the temperature is constant, so that a light bulb has a non-constant resistance because it heats up when used.