# 硬件 & 软件 Hardware and Software
# Grade 2 ( 5-7岁 ) 要掌握的程度
A computing system is composed of hardware and software. Hardware consists of physical components, while software provides instructions for the system. These instructions are represented in a form that a computer can understand.
Examples of hardware include screens to display information and buttons, keys, or dials to enter information. Software applications are programs with specific purposes, such as a web browser or game. A person may use a mouse (hardware) to click on a button displayed in a web browser (software) to navigate to a new web page. Computing systems convert instructions, such as “print,” “save,” or “crop,” into a special language that the computer can understand. At this level, understanding that computer information is encoded is appropriate, but the explicit understanding of “bits” is reserved for later grade levels.
Crosscutting Concept: Communication and Coordination Connections Within Framework: K–2.Algorithms and Programming. Algorithms; K–2.Algorithms and Programming.Control
计算机系统由硬件和软件组成.
- 硬件部分由实物组成, 包括用来显示信息的屏幕, 以及用来输入信息的按钮、键盘、拨盘.
- 而软件部分则是用来完成特定任务的程序代码 (代码必须以计算机能够理解的语法和形式来编写, 也就是说, 要遵守计算机编程语言的语法规则), 这些程序包括浏览器、游戏.
软硬件通常需要结合使用, 比如说, 我们用鼠标(硬件)点击浏览器(软件)上的按钮, 来切换到另一个浏览器的标签页.
计算机系统会将编程语言的代码 ( 比如 print、save、crop) 转换成计算机能够理解的机器语言(二进制语言).
对于这个阶段的学生来说, 可以适当了解一下“高级编程语言”如何转换成“机器语言”[1], 初步理解计算机信息的编码是需要的，但对"比特"的更深入的理解要留到以后的年级.
# Grade 5 ( 8-11岁 ) 要掌握的程度
Hardware and software work together as a system to accomplish tasks, such as sending, receiving, processing, and storing units of information as bits. Bits serve as the basic unit of data in computing systems and can represent a variety of information.
For example, a photo filter application (software) works with a camera (hardware) to produce a variety of effects that change the appearance of an image. This image is transmitted and stored as bits, or binary digits, which are commonly represented as 0s and 1s. All information, including instructions, is encoded as bits. Knowledge of the inner workings of hardware and software, number systems such as binary or hexadecimal, and how bits are represented in physical media are not priorities at this level.
Crosscutting Concepts: Communication and Coordination; Abstraction Connection Within Framework: 3–5.Data and Analysis.Storage
软件和硬件结合组成一个系统来共同完成比特信息[2]的发送、接收、处理和存储. “比特/bit”作为计算机中最基本的数据单位, 可以用来代表各种信息 (比如“ASCII 编码”、“Unicode编码“)
比如, 一个照片滤镜程序 (软件) 和相机 (硬件) 一起合作, 可以给照片添加各种效果. 在这个过程中, 照片的信息正是以“比特”(即二进制数字, 0和1)的形式来存储和传输的. 计算机中处理的所有信息, 包括代码, 都会被编码为0和1的比特信息. 这个阶段的孩子只要粗略了解上述关于比特的知识即可, 不需要详细了解比特信息的具体原理 (比如软硬件底层的运行过程、二进制或者十六进制、比特信息如何转换成人类能够看懂的信息)
# Grade 8 ( 11-14岁 ) 要掌握的程度
Hardware and software determine a computing system’s capability to store and process information. The design or selection of a computing system involves multiple considerations and potential tradeoffs, such as functionality, cost, size, speed, accessibility, and aesthetics.
The capability of a computing system is determined by the processor speed, storage capacity, and data transmission speed, as well as other factors. Selecting one computing system over another involves balancing a number of tradeoffs. For example, selecting a faster computer with more memory involves the tradeoffs of speed and cost. Choosing one operating system over another involves the tradeoff of capability and compatibility, such as which apps can be installed or which devices can be connected. Designing a robot requires choosing both hardware and software and may involve a tradeoff between the potential for customization and ease of use. The use of a device that connects wirelessly through a Bluetooth connection versus a device that connects physically through a USB connection involves a tradeoff between mobility and the need for an additional power source for the wireless device.
Crosscutting Concepts: System Relationships; Communication and Coordination Connection Within Framework: 6–8.Data and Analysis.Collection
软件和硬件共同决定了一个计算机系统能够如何存储和处理信息的功能. 但是挑选一个计算机系统不能光考虑功能, 而是需要综合考虑各种因素, 包括功能、成本、尺寸、处理速度、可用性、审美.
计算机系统的处理能力由多个因素决定, 包括CUP的速度、硬盘的存储容量、数据传输速度等等. 选择计算机系统需要权衡多方面因素. 比如说更快的速度、更大的内存和购买成本之间的权衡, 比如功能和兼容性之间的权衡 (“兼容性”是指这个计算机系统可以安装哪些应用程序、可以连接哪些外接设备, 比如说苹果电脑就不兼容很多工业软件).
选择计算机系统需要权衡, 我们设计计算机系统的时候同样也需要权衡. 比如, 设计一个机器人的硬件和软件时, 需要权衡系统的可定制性和易用性. 比如说, 考虑使用蓝牙无线连接还是有线连接时, 就需要在便携性和为无线设备准备额外电源之间进行权衡.
# Grade 12 ( 14-18岁 ) 要掌握的程度
Levels of interaction exist between the hardware, software, and user of a computing system. The most common levels of software that a user interacts with include system software and applications. System software controls the flow of information between hardware components used for input, output, storage, and processing.
At its most basic level, a computer is composed of physical hardware and electrical impulses. Multiple layers of software are built upon the hardware and interact with the layers above and below them to reduce complexity. System software manages a computing device’s resources so that software can interact with hardware. For example, text editing software interacts with the operating system to receive input from the keyboard, convert the input to bits for storage, and interpret the bits as readable text to display on the monitor. System software is used on many different types of devices, such as smart TVs, assistive devices, virtual components, cloud components, and drones. Knowledge of specific, advanced terms for computer architecture, such as BIOS, kernel, or bus, is not expected at this level.
Crosscutting Concepts: Abstraction; Communication and Coordination; System Relationships Connections Within Framework: 9–12.Networks and the Internet.Network Communication and Organization; 9–12.Algorithms and Programming.Variables; 9–12. Algorithms and Programming.Modularity
计算机系统的硬件、软件和用户之间存在着不同层次的互动. 用户和软件之间最常见的互动发生在操作系统和应用程序层面, 而操作系统(比如 Windows 系统、OSX 系统)则是用来控制输入、输出、存储、处理硬件之间的信息数据.
从最根本的层面来看, 计算机由物理硬件和电脉冲组成. 软件(包括操作系统层级和应用程序层级)是建立在物理硬件之上, 通过软件和硬件的交互, 来降低操作者使用计算机的复杂性.
操作系统在物理硬件之下, 管理计算机的各项资源, 使软件能够与硬件进行交互. 比如说, 文本编辑软件和操作系统与硬件设备之间的互动 -- 操作系统接收来自键盘的输入、将输入转换为比特信息存储到硬盘中, 并将这些0和1组成的比特信息, 解码为人类读得懂的语言信息, 显示在屏幕上. 操作系统运用在许多不同类型的设备上, 比如智能电视、辅助设备、虚拟组件、云组件、无人机.
对于这个阶段的学生, 只需要掌握上述知识即可, 不需要了解计算机结构的具体知识 (比如 BIOS、内核、总线).