Professional Terms专业术语calculator n.计算器notepad n.记事本Second, Windows allows you to run multiple programs at one time.第二，Windows允许用户同时使用多个程序。A computer with the ability to execute several programs simultaneously is called a time-sharing system.一台计算机如果具有同时执行多个程序的能力，则被称为分时系统。Later we will further examine how Windows performs time-sharing.稍后，我们还要进一步探讨Windows如何进行分时操作，Third ,Windows is called a desktop system.第三，Windows被称为桌面系统。Windows provides many of the abilities normally associated with items on your desk ,such as a notepad ,calculator and calendar.Windows具有很多处理一般与桌面有关项目的能力，如记事本、计算器和日历。
