📚 Glossary & Terminology Quick Memorisation Guide for CIE AS-Level Computer Science | CIE AS阶段计算机科学词汇术语速记指南
CIE AS-Level Computer Science introduces a broad range of technical vocabulary. Building a solid mental dictionary is the first step to mastering topics from binary logic to networking. This bilingual quick-reference guide pairs every essential term with a clear definition, helping you memorise and test yourself efficiently.
CIE AS阶段计算机科学引入了大量专业术语。建立扎实的术语词典是掌握从二进制逻辑到网络通信等各个主题的第一步。这份双语速记指南为每个关键术语配对了清晰的定义，帮助你高效记忆和自我检测。
1. Data Representation: Number Systems & Character Sets | 数据表示：数字系统与字符集
Bit — the smallest unit of data; a binary digit that can only be 0 or 1.
比特 — 数据的最小单位；一个只能取0或1的二进制数字。
Byte — a group of 8 bits, typically the smallest addressable unit of memory.
字节 — 由8个比特组成的一组，通常为内存中可寻址的最小单元。
Nibble — a group of 4 bits (half a byte), convenient for representing one hexadecimal digit.
半字节 — 由4个比特组成（半个字节），便于表示一位十六进制数字。
Binary (base 2) a number system that uses the digits 0 and 1; each column is a power of 2. Example: 1011₂ = 11₁₀.
二进制（基数为2） — 使用数字0和1的数字系统；每一位的权重为2的幂。例如：1011₂ = 11₁₀。
Hexadecimal (base 16) stem using digits 0-9 and letters A-F (10-15). One hex digit equals a nibble. Example: 2F₁₆ = 47₁₀.
十六进制（基数为16） — 使用数字0-9和字母A-F（10-15）的紧凑数字系统。一位十六进制数字等于一个半字节。例如：2F₁₆ = 47₁₀。
Binary Coded Decimal (BCD) — a representation where each decimal digit is encoded with its 4-bit binary equivalent (0-9). Example: 25₁₀ is 0010 0101 in BCD.
二进制编码的十进制 (BCD) — 一种用4位二进制表示每一位十进制数字（0-9）的编码方式。例如：十进制25的BCD码为0010 0101。
Two’s complement — a method for representing signed integers in binary. Negative numbers are formed by inverting all bits and adding 1. An 8-bit two’s complement number can range from -128 to +127.
二进制补码 — 一种用二进制表示有符号整数的方法。负数通过将所有位取反再加1形成。8位二进制补码可表示的范围为-128至+127。
Character set — a defined list of characters and their binary codes. Examples: ASCII (7-bit, 128 characters), Extended ASCII (8-bit, 256 characters), and Unicode (supporting many languages with code points up to U+10FFFF).
字符集 — 由字符及其二进制编码构成的列表。例如：ASCII（7位，128个字符），扩展ASCII（8位，256个字符），以及Unicode（支持多语言，码点最高至U+10FFFF）。
2. Data Representation: Sound, Images & Compression | 数据表示：声音、图像与压缩
Sampling rate — the number of sound samples taken per second, measured in hertz (Hz). A higher rate captures more detail but increases file size.
采样率 — 每秒采集的声音样本数，单位为赫兹（Hz）。较高的采样率能捕获更多细节，但会增大文件体积。
Sample resolution (bit depth) — the number of bits used to record each sample. Higher bit depth gives a greater dynamic range. CD quality uses 16 bits.
采样分辨率（位深） — 用于记录每个样本的比特数。位深越高，动态范围越大。CD质量使用16位。
Bit rate ssed audio, bit rate = sampling rate × sample resolution × number of channels.
比特率 — 每秒处理的比特数（bps）。对于无压缩音频，比特率 = 采样率 × 采样分辨率 × 声道数。
Pixel — the smallest addressable element of a digital image. Image resolution is the number of pixels in width × height (e.g. 1920×1080).
像素 — 数字图像中最小的可寻址元素。图像分辨率即宽度×高度的像素数量（如1920×1080）。
Colour depth — the number of bits used to represent the colour of a single pixel (e.g. 24 bits gives ~16.7 million colours).
颜色深度 — 用于表示单个像素颜色的比特数（例如24位可呈现约1670万色）。
Lossy compression — a compression technique that permanently removes some data to reduce file size. Used for JPEG, MP3; information cannot be perfectly restored.
有损压缩 — 通过永久性移除一部分数据来减小文件大小的压缩技术，用于JPEG、MP3等；数据无法完全复原。
Lossless compression — reduces file size without losing any original data; the file can be reconstructed exactly. Run-length encoding (RLE) is a simple lossless method.
无损压缩 — 在不丢失任何原始数据的前提下减小文件大小，可完全重建；行程长度编码（RLE）是一种简单的无损方法。
3. Communication Basics & Error Detection | 通信基础与错误检测
Serial transmission — data bits are sent one after another along a single wire. Suitable for long distances (USB, Ethernet).
串行传输 — 数据比特沿单根导线依次发送，适合长距离通信（USB、以太网）。
Parallel transmission — multiple bits are sent simultaneously over several wires. Faster over short distances but suffers from skew (bits arriving out of sync) on long cables.
并行传输 — 通过多根导线同时发送多个比特。短距离传输较快，但长线缆上易受偏移（比特不同步）影响。
Asynchronous transmission — data is sent in blocks with start and stop bits; no shared clock signal is needed. Commonly used in UART.
异步传输 — 数据以带有起始位和停止位的数据块发送；无需共享时钟信号，常用于UART通信。
Parity bit — an extra bit added to a binary string to make the total number of 1s either even (even parity) or odd (odd parity), used for simple error detection.
奇偶校验位 — 在二进制串后添加的附加位，使1的总数为偶数（偶校验）或奇数（奇校验），用于简单的错误检测。
Checksum — a calculated value (e.g. sum of data bytes) sent alongside data. The receiver recalculates and compares to detect corruption.
校验和 — 与数据一同发送的计算值（例如数据字节之和）。接收方重新
Published by TutorHao | Year 12 Computer Science Revision Series | aleveler.com
更多咨询请联系16621398022（同微信）
或截图后用「扫一扫 → 相册」选择本图