# What are zip files?

**URL:** <https://boards.straightdope.com/t/what-are-zip-files/239090>\
**Category:** Factual Questions\
**Created:** [April 9, 2004, 1:48am UTC](https://boards.straightdope.com/t/what-are-zip-files/239090 "2004-04-09T01:48:03Z")\
**Posts on this page:** 8\
**Page:** 1

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**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\
**Post date:** [April 9, 2004, 1:48am UTC](https://boards.straightdope.com/t/what-are-zip-files/239090/1 "2004-04-09T01:48:03Z")

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What are zip files?

Do you need a special/non-standard program to open them? One that isn’t part of Windows?

Is there a hightened virus risk?

Any & all info welcome.

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**Author:** ![TellMeI\_mNotCrazy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tellmei_mnotcrazy/32/3419_2.png) [@TellMeI\_mNotCrazy](https://boards.straightdope.com/u/TellMeI_mNotCrazy)\
**Post date:** [April 9, 2004, 1:51am UTC](https://boards.straightdope.com/t/what-are-zip-files/239090/2 "2004-04-09T01:51:40Z")

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Zip files are compressed packages of files to make them smaller, and easier to transfer. Don’t ask me how they work, someone else will have to explain that bit. XP has “unzipping” software included - the folder will have a zipper on it (clever, no?) but you can also download a program like [Winzip](http://www.winzip.com) to do the task - as well as create zip files of your own.

As for heightened virus risk, if you take the same precautions as you would any other file, there’s no difference in risk - a virus scanner will scan zip files with no problem.

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**Author:** ![jmizzou](https://avatars.discourse-cdn.com/v4/letter/j/edb3f5/32.png) [@jmizzou](https://boards.straightdope.com/u/jmizzou)\
**Post date:** [April 9, 2004, 1:57am UTC](https://boards.straightdope.com/t/what-are-zip-files/239090/3 "2004-04-09T01:57:28Z")

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More than you ever wanted to know about file compression [here](http://computer.howstuffworks.com/file-compression.htm).

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**Author:** ![rjk](https://avatars.discourse-cdn.com/v4/letter/r/ed655f/32.png) [@rjk](https://boards.straightdope.com/u/rjk)\
**Post date:** [April 9, 2004, 2:00am UTC](https://boards.straightdope.com/t/what-are-zip-files/239090/4 "2004-04-09T02:00:41Z")

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Look [here](http://en.wikipedia.org/wiki/Zip_(file_format)) for a description.

The author, Phil Katz, released the format for public use without charge, so there are dozens of Zip programs out there, most of them free and many nicer to use than WinZip.

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**Author:** ![cstamets](https://avatars.discourse-cdn.com/v4/letter/c/958977/32.png) [@cstamets](https://boards.straightdope.com/u/cstamets)\
**Post date:** [April 9, 2004, 2:07am UTC](https://boards.straightdope.com/t/what-are-zip-files/239090/5 "2004-04-09T02:07:23Z")

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> [@TellMeI'mNotCrazy](#):
>
> Zip files are compressed packages of files to make them smaller, and easier to transfer. Don’t ask me how they work, someone else will have to explain that bit. XP has “unzipping” software included - the folder will have a zipper on it (clever, no?) but you can also download a program like [Winzip](http://www.winzip.com) to do the task - as well as create zip files of your own.  
> .

Amazingly, a large number of people don’t realize you can also create zip files in XP. Right-click on what you want to zip, go to Send to, then Compressed (zipped) folder.

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**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\
**Post date:** [April 9, 2004, 4:04am UTC](https://boards.straightdope.com/t/what-are-zip-files/239090/6 "2004-04-09T04:04:25Z")

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From the question about virus risk, I’m guessing that the OP got one in the mail that he doesn’t know what it is. In that case, yes, it is a virus. It takes a little more effort to get infected by it, since you need to first unzip the program and then run it, but the advantage (to the virus writer) is that it’s much harder for a mail filter to catch it. It may even be a password-protected zip file, with the password provided in the body of the e-mail, which would make it almost impossible for a scanner to catch it.

Whenever you get _anything at all_ in an e-mail that you don’t know what it is, assume it’s a virus, and delete it unopened.

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**Author:** ![TJdude825](https://avatars.discourse-cdn.com/v4/letter/t/dec6dc/32.png) [@TJdude825](https://boards.straightdope.com/u/TJdude825)\
**Post date:** [April 9, 2004, 4:12am UTC](https://boards.straightdope.com/t/what-are-zip-files/239090/7 "2004-04-09T04:12:32Z")

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You can also compress an entire directory, or even your entire hard drive, if you really want to. The only reason you’d want to, that I know of, is to create more space on your hard drive. This will slow your computer’s performance, though.

[Howstuffworks.com](http://Howstuffworks.com) has an article on [how file compression works](http://computer.howstuffworks.com/file-compression.htm).

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**Author:** ![Shrinking\_Violet](https://avatars.discourse-cdn.com/v4/letter/s/df705f/32.png) [@Shrinking\_Violet](https://boards.straightdope.com/u/Shrinking_Violet)\
**Post date:** [April 9, 2004, 12:54pm UTC](https://boards.straightdope.com/t/what-are-zip-files/239090/8 "2004-04-09T12:54:01Z")

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Zipping a file or folder is also an easy way to password protect it on your hard drive … at least with Winzip (I’m unfamiliar with other zip programs).
