The triboelectric series lists different materials according to the order in which they become positively charged or negatively charged on being rubbed together. For any two materials, the one higher on the list becomes positively charged when rubbed with one lower on the list, which becomes negatively charged.

Air
Asbestos
Your very dry hand
Rabbit fur
Glass
Your hair
Nylon
Wool
Fur
Lead
Silk
Aluminum
Cotton
Steel
Wood
Hard rubber
Nickel, Copper
Brass, Silver
Gold, Platinum
Acetate, Rayon
Polyester
Polyurethane
Polyvinyl Chloride
Silicon
Teflon

It must be noticed, however, that there are several versions of the triboelectric series, and materials are not always positioned in the same relative order. This is due to the fact that the result of rubbing two materials depends also on other parameters, such as the quality of their surfaces, their chemical composition, the temperature, the humidity of the air, and so forth..