Greg’s ppt (locked) for resistor colour codes and introducing surface mount components and codes on SMC.
I do still like to keep colour codes simple and not so much use the word ‘multiplier’, but to use the term ‘number of zeros’. The term multiplier is more relevant for gold and silver last colour value ident bands.
The world has changed a lot since standard resistor body colour codes were introduced. The word standard here meaning that prior to the bands, there were coloured dots on a coloured body. (1940/50 and earlier). Now days though the use of micro electronics and low power consumptions sees much more equipment using surface mount technology and these components do not use colour.
Through hole resistors, and power resistors especially are still used in high power dissipation equipment, such as power supplies, welders, transmitters, inverters.