In Amsterdam, the term of coffee has come to mean a place where hashish and marijuana are available. Visiting the Netherlands from the prohibitionist world outside can be a very instructive experience. It is completely wrong for us to assume that this country is not civilized. It is not that Holland is ruled by a bunch of hippies, but that have a more rational attitude to facts of life such as drugs and prostitution.
There are many types of coffee shops in Amsterdam: Some are relaxing, others are alive with loud music or decorations. Because people around enjoy them, any aggression is not acceptable. You can smoke from your own bag, but you must buy something to sit there. Some general rules that owners of coffee shops in Amsterdam are expected to follow are: Minimum Age 18 years and required identification, you can not have alcohol and hard drugs in coffee shops, in some cafes you may not use mobile phones, you must consume.
Each café offers several types of grass and hash, usually there is a menu to choose from. Prices vary depending on the quality (about 5 euros per gram). You can always ask the staff about the strength and overall effects of hashish. You can also ask for a pipe, wrapper or filter tips.