Zip Files
What is a Zip file
A Zip file is a compressed file containing 1 or more
files/folders and normally has a filename which ends with .zip.
There are a variety of reasons why you would want to compress files namely to;
send files more quickly over the internet; send several large files, by
email, as one easy-to-manage zipped attachment; to save space on a restricted
user area.
Please note: Emails
containing zip files require the zip file to be password-protected or the
University's security system will remove the zip file when the email is
sent/received. There is also a maximum size limit of 5Mb per email. Click here for notes on
Password Protecting a Zip File.
Zipping files in
Windows XP
Windows XP has built-in ZIP
file support for such files. See below for instructions on how to Create a Zip
File in Windows XP. There are also third-party programs such as WinZip, Enzip
and WinRar which create and open them.
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To create a ZIP file in
Windows XP
- Right click on the file, folder, or selection of files you want to
zip, and click on the Send To menu option and then
choose Compressed (zipped) Folder.
- In the example:
the files in the "Leaflet" folder have been sent
to a Compressed (zipped) folder which has automatically be named
"Leaflet". Compressed files are identified by the zipper on the folder
icon.
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Understanding compression
- Depending on what type of file you are dealing with, compressing
files can reduce their size by as much as 80% or 90%. A bitmap file is
usually not compressed so is typically much larger than a compressed
file format such as jpeg.
- In the example: the zipped folder contains a mixture of
wordprocessing, graphic and publishing files. Note how the bitmap file,
which started off at almost 2.5mb, has been compressed a massive 83%, to
396k
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- The Ratio of compression is shown in percentage. The "packed size"
is the size after compression.
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Password Protecing a Zip File
- Right-click on a zip file and click
Open With then Compressed
Zipped Folders.
- Now click File then Add a Password. Input a password of your choice,
confirm it then click Ok.
- People will be able to see the contents of the zip file but will
need the password to extract them.
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Viewing and Extracting
files from a Zipped file
- If you want to view the files in a zipped file simply double-click
the zipped folder.
- To extract files from a zipped folder, right-click on a zip file and
click Open With then Compressed Zipped Folders.
- Now click File then Extract All, then Next. By default, a folder
with the same name as the zip file will be created.
If you are happy
with this click Next.
- Note: you may need to provide a password.
- Click Finish to see the contents of the created folder.
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Please note: if a third-party Zip
program, like those mentioned above, has been installed on the computer then the
menu entry "Compressed (zipped) Folder" may be replaced by that program's name
and choosing that entry will launch the program's own zip method. |
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