[[File:Resistors.svg|150px|right|thumb|Two version of the electronic symbol for a resistor. The top is the American and Japanese convention. The bottom is the [https://en.wikipedia.org/wiki/International_Electrotechnical_Commission IEC] standard.]]
[[File:Bsp2.svg|150px|right|thumb|R1 and R2 are connected in series, they're connected in parallel to R3.]]
[[File:Voltage divider.svg|150px|right|thumb|A voltage divider.]]
'''Resistance''' ('''R''') is the measure in Ohms (Ω) of opposition to the flow of electric current in a circuit.