Furthermore, there are dry shampoos; powders that remove sebum from hair by soaking it up prior to being combed out.
People often use dry shampoo if they would like to postpone their hair wash or simply to save time.
Most hairdressers in Canada, US and Europe and Latin America, offer a hair wash as a service before or after a haircut.
In the backward version (the more common), the client sits in a chair, and leans their head back into a sink, with the hairdresser standing behind them.
In this style, the client sits in a chair, while a hairdresser applies shampoo to their hair and adds water.