《Operating System Concepts》學習第 7 天，p34-p40 總結，總計 7 頁。

一、技術總結

1.virtualization(虛擬化)

(1)定義

A technology for abstracting the hardware of a single computer into several different execution environments, thereby creating the illusion that each environment is running on its own private computer.

2.distributed system(分布式系統)

(1)定義

A distributed system is a collection of physically separate, possibly heterogeneous computer systems that are networked to provide users with access to the various resources that the system maintains.

二、英語總結(生詞：2)

1.escalate

(1)escalator: escalade(scala, "ladder") + -ator

c. a moving staircase(自動手扶梯，手扶電梯)。

(2)escalate: back-formation from escalator.

(3)escalation: derived noun from escalate.

vi/vt. to become greater. the root of escalate connects to the idea of "climbing" or "rising", which involved into the concept of increasing or intensifying sth progressively.

示例：However, a user sometimes needs to escalate privileges to gain extra permissions for an activity(《Operating System Concepts》第 34 頁)。

2.illusion

(1)illusion: il-(a variant of "in") + ludere("to play")

c/u. a deceptive appearance or impression(幻覺).

示例：Virtualization is a technology that allows us to abstract the hardware of a single computer (the CPU, memory, disk drives, network interface cards, and so forth) into several different execution environments, thereby creating the illusion that each separate environment is running on its own private computer(《Operating System Concepts》第 34 頁)。

關于英語的注解同步更新匯總到 https://github.com/codists/English-In-CS-Books 倉庫。

三、其它

今天了解了 virtualization 的概念。

四、參考資料

1. 編程

(1) Abraham Silberschatz，Peter Baer Galvin，Greg Gagne《Operating System Concepts》：https://book.douban.com/subject/30272539/

2. 英語

(1) Etymology Dictionary：https://www.etymonline.com

(2) Cambridge Dictionary：https://dictionary.cambridge.org

歡迎搜索及關注：編程人(a_codists)