A collection of new and changed modules and macros that provide a dded program function or hardware support. Selectable units are shipped independently of a release and are installed singly or in groups at the option of the user.; 一種新的及已更改的模塊和宏功能的組合,提供附加的程序功能或?qū)τ布闹С帧？蛇x 部件可按用戶的選擇與某一版本分開發(fā)運(yùn),單個或成組安裝。