1 The Simple Explanation
No jargon version.
A ZIP file is a container that holds other files inside it. Think of it as a digital suitcase. You put files in, zip it shut, and now you have one single item instead of many. That suitcase is also compressed, meaning the contents take up less space than they would loose.
When you receive a ZIP file, you need to "unzip" it — which means opening that suitcase and taking the files out — before you can use the files inside.
2 Why Do People Use ZIP Files?
Three main reasons.
To send multiple files at once. Instead of attaching 47 separate documents to an email, you put them all in one ZIP file and attach just that. One download, done.
To reduce file size. ZIP compression shrinks files, sometimes dramatically. A 100MB folder might become a 30MB ZIP file. This means faster uploads, downloads, and less email storage used.
To protect files with a password. An encrypted ZIP file can only be opened by someone who knows the password. This is why banks, law firms, and businesses use them when sending sensitive documents.
3 How to Recognize a ZIP File
What to look for.
File extension: The file name ends in .zip — for example, Documents.zip or Photos_2024.zip.
Icon: On Windows, ZIP files look like a folder with a zipper on it. On Mac, they look like a file with a zipper or a small rectangle.
In email: ZIP files often appear as paperclip attachments. Your email client might show a preview of the contents or just the file name.
4 Ready to Open One?
Head to our step-by-step guides.