In modern buildings many different sorts of glass are used for many different purposes, e.g. shop windows, entrances, winter gardens and roofing. It is also used inside for partitioning or sign boards. The skilled glaziers must know how and when to use the different glasses (plate glass, insolation glass, frosted and profile glass, etc.). They must also carry out preparation work in the workshop such as cutting to size, boring holes and cutting out sections so that the glass can be efficiently mounted on site. Knowledge of mounting materials and procedures such as framing and frame work is also important.