照片里的“元数据”是什么，为什么要注意？
What is photo 'metadata' and why be careful?
元数据是藏在照片里的附加信息，比如拍摄时间、相机型号，还有可能包含 GPS 位置。发原图给陌生人可能泄露你常在哪，发前可关掉位置信息或发压缩图。
Metadata is hidden info in a photo—time, camera, and possibly GPS location. Sending originals can reveal where you are; turn off location or send compressed copies.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#元数据 #隐私 #定位
有损压缩和无损压缩有什么区别？
What is the difference between lossy and lossless compression?
有损会丢掉一些人耳人眼难察觉的信息（如 MP3、JPG），文件更小；无损（如 ZIP、FLAC）不丢信息，解压完全复原，但压得没那么小。听歌收藏常选无损，发微信用有损更省流量。
Lossy drops barely-noticeable info (MP3, JPG) for smaller files; lossless (ZIP, FLAC) keeps everything and restores exactly, but compresses less. Collect music lossless; send via WeChat lossy to save data.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#有损 #无损 #压缩
什么是 PDF，为什么发文件常用它？
What is a PDF and why is it used to send files?
PDF 是一种固定版式的文件格式，不管谁打开，排版、字体都和原来一样，不会乱跑。适合发合同、简历、说明书，对方看到的跟你的一模一样。
PDF fixes layout so it looks identical on any device—no shifting text. Great for contracts, resumes and manuals; the reader sees exactly what you made.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#PDF #格式 #文档
为什么要经常备份照片和文件？
Why back up photos and files regularly?
手机丢、进水、中病毒都会让数据一下子没了。备份就是多存一份到云盘或电脑，坏掉一份还有另一份。记住口诀：两份不在同一处，才叫安全。
Loss, water or malware can wipe data instantly. A backup is a second copy on cloud or PC, so one failure leaves another. Rule: two copies in different places is safe.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#备份 #数据 #安全
常说的 1080p、4K 是什么意思？
What do 1080p and 4K mean?
它们指视频的清晰度，数字越大越清楚。1080p 约 200 万像素一行，4K 是它的四倍左右，画面更细腻，但更费流量和带宽。
They mark video sharpness; bigger numbers are clearer. 1080p is about 2 million pixels per frame; 4K is roughly four times that—crisper but heavier on data and bandwidth.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#1080p #4K #清晰度
什么是屏幕的“刷新率”（如 60Hz、120Hz）？
What is screen 'refresh rate' like 60Hz or 120Hz?
刷新率是屏幕每秒重画多少次画面。60Hz 每秒 60 次，120Hz 更顺滑，滑动和游戏更跟手。高刷新率更爽，但也更费电。
Refresh rate is how many times per second the screen redraws. 60Hz is 60 times; 120Hz feels smoother in scrolling and games. Higher is nicer but drains battery faster.
难度 进阶 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#刷新率 #屏幕 #流畅
什么是文件压缩（比如 zip）？
What is file compression, like a zip?
压缩是把文件“挤一挤”变小，方便发送或省空间。zip 能把很多文件打成一个小包，解压后又恢复原样。就像把衣服压进行李箱。
Compression squeezes files smaller for sending or saving space. A zip packs many files into one small bundle; unzip restores them—like pressing clothes into a suitcase.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#压缩 #zip #文件
JPG 和 PNG 图片格式有什么不同？
How do JPG and PNG image formats differ?
JPG 适合照片，文件小但会丢失一点细节；PNG 适合图标、文字和需要透明背景的图，质量更好、文件更大。发照片常用 JPG，做带透明底的图用 PNG。
JPG suits photos—small but loses a bit of detail. PNG suits icons, text and transparent backgrounds—better quality, bigger file. Use JPG for photos, PNG for transparency.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#JPG #PNG #格式
什么是“带宽”，为什么叫“宽”？
What is 'bandwidth' and why 'width'?
带宽像水管有多粗，决定同一时间能传送多少数据。带宽越宽，下载越快、看高清越顺畅。它和网速有关，但不是同一回事。
Bandwidth is like pipe width—how much data can flow at once. Wider means faster downloads and smoother HD. It relates to speed but isn't the same thing.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#带宽 #网速 #网络
什么是云盘（网盘）？
What is cloud storage (a cloud drive)?
云盘是把文件存在别人家的大服务器上，你用账号随时上网取。手机坏了也不怕，照片视频还在“云”里，换台设备登录就能看。
Cloud storage keeps your files on someone else's big servers you reach by account. If your phone breaks, photos stay 'in the cloud' and you see them on any device.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#云盘 #备份 #存储
什么是 U 盘，它有什么用？
What is a USB drive and what is it for?
U 盘是个小得能挂钥匙扣的随身存储器，插进电脑就能存照片、拷文件。它不像云盘要上网，拔下来就能带走。
A USB drive is a tiny pocket storage you plug into a computer to save or copy files. Unlike cloud, it needs no internet—unplug and take it anywhere.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#U盘 #存储 #便携
什么是照片的“分辨率”？
What is a photo's 'resolution'?
分辨率是照片由多少小点（像素）组成。点越多，放大后越清楚；点少，放大就糊。手机常说的 1200 万像素就是约 1200 万个小点。
Resolution is how many dots (pixels) a photo has. More dots stay clear when zoomed; fewer get blurry. '12 megapixels' means about 12 million dots.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#分辨率 #像素 #照片
什么是“流媒体”（在线看视频、听歌）？
What is 'streaming' (watching video or music online)?
流媒体是边下载边播放，不用等整部下完。你点的那刻，服务器一小段一小段把内容传过来，所以叫“流”。看电影、听歌大多都是流媒体。
Streaming plays while downloading, so you don't wait for the whole file. The server sends it in small chunks as you watch—hence 'stream'. Most video and music is streaming.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#流媒体 #在线 #播放
什么是电子书，和纸质书有什么不同？
What is an e-book and how is it different from paper?
电子书是把文字存在手机或阅读器里的书，能调字号、搜关键词、随身带几百本。它省纸、方便，但有些人还是喜欢翻纸质书的感觉。
An e-book stores text on a phone or reader; you resize fonts, search words and carry hundreds. It saves paper and is handy, though some still love paper's feel.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Charles Petzold,《Code: The Hidden Language of Computer Hardware and Software》第2版,Microsoft Press,2022
C. Petzold, Code, 2nd ed., Microsoft Press, 2022; Chinese ed.《编码》
#电子书 #阅读 #数字